Bridged metallocene catalyst systems with switchable hydrogen and comonomer effects

ABSTRACT

The present invention provides polymerization processes utilizing an ansa-metallocene catalyst system for the production of olefin polymers. Polymers produced from the polymerization processes have properties that vary based upon the presence or the absence of hydrogen and/or comonomer in the polymerization process.

REFERENCE TO RELATED APPLICATION

This application is a divisional application of co-pending U.S. patentapplication Ser. No. 12/899,753, filed on Oct. 7, 2010, now U.S. Pat.No. 8,637,616, the disclosure of which is incorporated herein byreference in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to the field of olefinpolymerization catalysis, metallocene catalyst compositions, methods forthe polymerization and copolymerization of olefins, and polyolefins.

SUMMARY OF THE INVENTION

Disclosed herein are polymerization processes employing bridgedmetallocene catalyst systems for the production of olefin polymers. Theolefin polymers produced from the disclosed polymerization processesdemonstrate unexpected properties based upon the presence or absence ofhydrogen and/or comonomer in the polymerization process.

In accordance with an aspect of the present invention, a catalystcomposition is provided, and this catalyst composition comprises anansa-metallocene compound and an activator or an activator-support. Inanother aspect, an olefin polymerization process is provided and, inthis aspect, the process comprises contacting a catalyst compositionwith an olefin monomer and optionally an olefin comonomer underpolymerization conditions to produce an olefin polymer, wherein thecatalyst composition comprises an ansa-metallocene compound and anactivator or an activator-support.

In these catalyst compositions and polymerization processes, theansa-metallocene compound has formula (I):E(Cp^(A)R^(A) _(m))(Cp^(B)R^(B) _(n))MX_(q);wherein:

M is Ti, Zr, Hf, Cr, Sc, Y, La, or a lanthanide;

Cp^(A) and Cp^(B) independently are a cyclopentadienyl, indenyl, orfluorenyl group;

each R^(A) and R^(B) independently is H or a hydrocarbyl,hydrocarbylsilyl, hydrocarbylamino, or hydrocarbyloxide group having upto 18 carbon atoms;

E is a bridging chain of 3 to 8 carbon atoms or 2 to 8 silicon,germanium, or tin atoms, wherein any substituents on atoms of thebridging chain independently are H or a hydrocarbyl group having up to18 carbon atoms;

each X independently is F; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄;OBR₂ or SO₃R, wherein R is an alkyl or aryl group having up to 18 carbonatoms; or a hydrocarbyloxide group, a hydrocarbylamino group, or ahydrocarbylsilyl group, any of which having up to 18 carbon atoms;

m is 0, 1, 2, 3, or 4;

n is 0, 1, 2, 3, or 4;

q is 2 when M is Ti, Zr, or Hf; and

q is 1 when M is Cr, Sc, Y, La, or a lanthanide.

Polymers produced from the polymerization of olefins using these bridgedmetallocene catalyst systems, resulting in homopolymers, copolymers, andthe like, can be used to produce various articles of manufacture.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 presents a plot of the molecular weight distributions of thepolymers of Examples 3, 5, and 7.

FIG. 2 presents a plot of the molecular weight distributions of thepolymers of Examples 2, 6, and 15.

FIG. 3 presents a plot of the molecular weight distributions of thepolymers of Examples 2, 3, and 16.

FIG. 4 presents a plot of the molecular weight distributions of thepolymers of Examples 6-7 and 44-45.

FIG. 5 presents a plot of the radius of gyration versus the logarithm ofmolecular weight for a linear standard and the polymers of Examples 2-3and 6-7.

FIG. 6 presents a plot of Delta versus the log G* (complex modulus) forthe polymers of Examples 2-3 and 6-7.

FIG. 7 presents a plot of catalyst activity versus initial 1-hexenecomonomer concentration for Examples 2-7 and 40-45.

FIG. 8 presents a plot of first order models of catalyst activity versusinitial 1-hexene comonomer concentration for Examples 2-7 and 40-45.

FIG. 9 presents a plot of the logarithm of melt index versus hydrogenfeed concentration for the polymers of Examples 4-5, 7, and 17-24.

FIG. 10 presents a plot of the high load melt index versus the meltindex for the polymers of Examples 4 and 17-24.

FIG. 11 presents a plot of zero shear viscosity versus weight-averagemolecular weight, specifically, log(η₀) versus log(Mw), for the polymersof Examples 2-3, 5-7, 18, 44-45, and 66-67.

DEFINITIONS

To define more clearly the terms used herein, the following definitionsare provided. To the extent that any definition or usage provided by anydocument incorporated herein by reference conflicts with the definitionor usage provided herein, the definition or usage provided hereincontrols.

The term “polymer” is used herein generically to include olefinhomopolymers, copolymers, terpolymers, and so forth. A copolymer isderived from an olefin monomer and one olefin comonomer, while aterpolymer is derived from an olefin monomer and two olefin comonomers.Accordingly, “polymer” encompasses copolymers, terpolymers, etc.,derived from any olefin monomer and comonomer(s) disclosed herein.Similarly, an ethylene polymer would include ethylene homopolymers,ethylene copolymers, ethylene terpolymers, and the like. As an example,an olefin copolymer, such as an ethylene copolymer, can be derived fromethylene and a comonomer, such as 1-butene, 1-hexene, or 1-octene. Ifthe monomer and comonomer were ethylene and 1-hexene, respectively, theresulting polymer would be categorized an as ethylene/1-hexenecopolymer.

In like manner, the scope of the term “polymerization” includeshomopolymerization, copolymerization, terpolymerization, etc. Therefore,a copolymerization process would involve contacting one olefin monomer(e.g., ethylene) and one olefin comonomer (e.g., 1-hexene) to produce acopolymer.

Hydrogen in this disclosure can refer to either hydrogen (H₂) which isused in a polymerization process, or a hydrogen atom (H), which can bepresent, for example, on a metallocene compound. When used to denote ahydrogen atom, hydrogen will be displayed as “H,” whereas if the intentis to disclose the use of hydrogen in a polymerization process, it willsimply be referred to as “hydrogen.”

The term “co-catalyst” is used generally herein to refer toorganoaluminum compounds that can constitute one component of a catalystcomposition. Additionally, “co-catalyst” can refer to other componentsof a catalyst composition including, but not limited to, aluminoxanes,organoboron or organoborate compounds, and ionizing ionic compounds, asdisclosed herein, when used in addition to an activator-support. Theterm “co-catalyst” is used regardless of the actual function of thecompound or any chemical mechanism by which the compound may operate. Inone aspect of this invention, the term “co-catalyst” is used todistinguish that component of the catalyst composition from themetallocene compound(s).

The terms “chemically-treated solid oxide,” “activator-support,”“treated solid oxide compound,” and the like, are used herein toindicate a solid, inorganic oxide of relatively high porosity, which canexhibit Lewis acidic or Brønsted acidic behavior, and which has beentreated with an electron-withdrawing component, typically an anion, andwhich is calcined. The electron-withdrawing component is typically anelectron-withdrawing anion source compound. Thus, the chemically-treatedsolid oxide can comprise a calcined contact product of at least onesolid oxide with at least one electron-withdrawing anion sourcecompound. Typically, the chemically-treated solid oxide comprises atleast one acidic solid oxide compound. The terms “support” and“activator-support” are not used to imply these components are inert,and such components should not be construed as an inert component of thecatalyst composition. The activator-support of the present invention canbe a chemically-treated solid oxide. The term “activator,” as usedherein, refers generally to a substance that is capable of converting ametallocene component into a catalyst that can polymerize olefins, orconverting a contact product of a metallocene component and a componentthat provides an activatable ligand (e.g., an alkyl, a hydride) to themetallocene, when the metallocene compound does not already comprisesuch a ligand, into a catalyst that can polymerize olefins. This term isused regardless of the actual activating mechanism. Illustrativeactivators include activator-supports, aluminoxanes, organoboron ororganoborate compounds, ionizing ionic compounds, and the like.Aluminoxanes, organoboron or organoborate compounds, and ionizing ioniccompounds generally are referred to as activators if used in a catalystcomposition in which an activator-support is not present. If thecatalyst composition contains an activator-support, then thealuminoxane, organoboron or organoborate, and ionizing ionic materialsare typically referred to as co-catalysts.

The term “fluoroorgano boron compound” is used herein with its ordinarymeaning to refer to neutral compounds of the form BY₃. The term“fluoroorgano borate compound” also has its usual meaning to refer tothe monoanionic salts of a fluoroorgano boron compound of the form[cation]⁺[BY₄]⁻, where Y represents a fluorinated organic group.Materials of these types are generally and collectively referred to as“organoboron or organoborate compounds.”

The term “metallocene,” as used herein, describes a compound comprisingat least one η³ to η⁵-cycloalkadienyl-type moiety, wherein η³ toη⁵-cycloalkadienyl moieties include cyclopentadienyl ligands, indenylligands, fluorenyl ligands, and the like, including partially saturatedor substituted derivatives or analogs of any of these. Possiblesubstituents on these ligands may include H, therefore this inventioncomprises partially saturated ligands such as tetrahydroindenyl,tetrahydrofluorenyl, octahydrofluorenyl, partially saturated indenyl,partially saturated fluorenyl, substituted partially saturated indenyl,substituted partially saturated fluorenyl, and the like. In somecontexts, the metallocene is referred to simply as the “catalyst,” inmuch the same way the term “co-catalyst” is used herein to refer to, forexample, an organoaluminum compound. Metallocene also is usedgenerically herein to encompass dinuclear metallocene compounds, i.e.,compounds comprising two metallocene moieties linked by a connectinggroup, such as an alkenyl group resulting from an olefin metathesisreaction or a saturated version resulting from hydrogenation orderivatization.

The terms “catalyst composition,” “catalyst mixture,” “catalyst system,”and the like, do not depend upon the actual product or compositionresulting from the contact or reaction of the initial components of theclaimed catalyst composition/mixture/system, the nature of the activecatalytic site, or the fate of the co-catalyst, the metallocenecompound(s), any olefin monomer used to prepare a precontacted mixture,or the activator (e.g., activator-support), after combining thesecomponents. Therefore, the terms “catalyst composition,” “catalystmixture,” “catalyst system,” and the like, encompass the initialstarting components of the composition, as well as whatever product(s)may result from contacting these initial starting components, and thisis inclusive of both heterogeneous and homogenous catalyst systems orcompositions.

The term “contact product” is used herein to describe compositionswherein the components are contacted together in any order, in anymanner, and for any length of time. For example, the components can becontacted by blending or mixing. Further, contacting of any componentcan occur in the presence or absence of any other component of thecompositions described herein. Combining additional materials orcomponents can be done by any suitable method. Further, the term“contact product” includes mixtures, blends, solutions, slurries,reaction products, and the like, or combinations thereof. Although“contact product” can include reaction products, it is not required forthe respective components to react with one another. Similarly, the term“contacting” is used herein to refer to materials which may be blended,mixed, slurried, dissolved, reacted, treated, or otherwise contacted insome other manner.

The term “precontacted” mixture is used herein to describe a firstmixture of catalyst components that are contacted for a first period oftime prior to the first mixture being used to form a “postcontacted” orsecond mixture of catalyst components that are contacted for a secondperiod of time. Typically, the precontacted mixture describes a mixtureof metallocene compound (one or more than one), olefin monomer (ormonomers), and organoaluminum compound (or compounds), before thismixture is contacted with an activator-support(s) and optionaladditional organoaluminum compound. Thus, precontacted describescomponents that are used to contact each other, but prior to contactingthe components in the second, postcontacted mixture. Accordingly, thisinvention may occasionally distinguish between a component used toprepare the precontacted mixture and that component after the mixturehas been prepared. For example, according to this description, it ispossible for the precontacted organoaluminum compound, once it iscontacted with the metallocene compound and the olefin monomer, to havereacted to form at least one different chemical compound, formulation,or structure from the distinct organoaluminum compound used to preparethe precontacted mixture. In this case, the precontacted organoaluminumcompound or component is described as comprising an organoaluminumcompound that was used to prepare the precontacted mixture.

Additionally, the precontacted mixture can describe a mixture ofmetallocene compound(s) and organoaluminum compound(s), prior tocontacting this mixture with an activator-support(s). This precontactedmixture also can describe a mixture of metallocene compound(s), olefinmonomer(s), and activator-support(s), before this mixture is contactedwith an organoaluminum co-catalyst compound or compounds.

Similarly, the term “postcontacted” mixture is used herein to describe asecond mixture of catalyst components that are contacted for a secondperiod of time, and one constituent of which is the “precontacted” orfirst mixture of catalyst components that were contacted for a firstperiod of time. Typically, the term “postcontacted” mixture is usedherein to describe the mixture of metallocene compound(s), olefinmonomer(s), organoaluminum compound(s), and activator-support(s) formedfrom contacting the precontacted mixture of a portion of thesecomponents with any additional components added to make up thepostcontacted mixture. Often, the activator-support comprises achemically-treated solid oxide. For instance, the additional componentadded to make up the postcontacted mixture can be a chemically-treatedsolid oxide (one or more than one), and optionally, can include anorganoaluminum compound which is the same as or different from theorganoaluminum compound used to prepare the precontacted mixture, asdescribed herein. Accordingly, this invention may also occasionallydistinguish between a component used to prepare the postcontactedmixture and that component after the mixture has been prepared.

Although any methods, devices, and materials similar or equivalent tothose described herein can be used in the practice or testing of theinvention, the typical methods, devices and materials are hereindescribed.

All publications and patents mentioned herein are incorporated herein byreference for the purpose of describing and disclosing, for example, theconstructs and methodologies that are described in the publications,which might be used in connection with the presently describedinvention. The publications discussed throughout the text are providedsolely for their disclosure prior to the filing date of the presentapplication. Nothing herein is to be construed as an admission that theinventors are not entitled to antedate such disclosure by virtue ofprior invention.

For any particular compound disclosed herein, any general or specificstructure presented also encompasses all conformational isomers,regioisomers, and stereoisomers that may arise from a particular set ofsubstituents, unless stated otherwise. Similarly, unless statedotherwise, the general or specific structure also encompasses allenantiomers, diastereomers, and other optical isomers whether inenantiomeric or racemic forms, as well as mixtures of stereoisomers, aswould be recognized by a skilled artisan.

Applicants disclose several types of ranges in the present invention.These include, but are not limited to, a range of number of atoms, arange of weight ratios, a range of molar ratios, a range of surfaceareas, a range of pore volumes, a range of catalyst activities, a rangeof temperatures, a range of times, and so forth. When Applicantsdisclose or claim a range of any type, Applicants' intent is to discloseor claim individually each possible number that such a range couldreasonably encompass, including end points of the range as well as anysub-ranges and combinations of sub-ranges encompassed therein. Forexample, when the Applicants disclose or claim a chemical moiety havinga certain number of carbon atoms, Applicants' intent is to disclose orclaim individually every possible number that such a range couldencompass, consistent with the disclosure herein. For example, thedisclosure that a moiety is a C₁ to C₁₈ hydrocarbyl group, or inalternative language a hydrocarbyl group having up to 18 carbon atoms,as used herein, refers to a moiety that can be selected independentlyfrom a hydrocarbyl group having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, or 18 carbon atoms, as well as any range betweenthese two numbers (for example, a C₁ to C₈ hydrocarbyl group), and alsoincluding any combination of ranges between these two numbers (forexample, a C₂ to C₄ and a C₁₂ to C₁₆ hydrocarbyl group).

Similarly, another representative example follows for the molar ratio ofolefin comonomer to olefin monomer provided in one aspect of thisinvention. By a disclosure that the olefin comonomer:monomer ratio canbe in a range from about 0.001:1 to about 0.06:1, Applicants intend torecite that the comonomer:monomer ratio can be about 0.001:1, about0.002:1, about 0.003:1, about 0.004:1, about 0.005:1, about 0.006:1,about 0.007:1, about 0.008:1, about 0.009:1, about 0.01:1, about0.015:1, about 0.02:1, about 0.025:1, about 0.03:1, about 0.035:1, about0.04:1, about 0.045:1, about 0.05:1, about 0.055:1, or about 0.06:1.Additionally, the comonomer:monomer ratio can be within any range fromabout 0.001:1 to about 0.06:1 (for example, from about 0.01:1 to about0.05:1), and this also includes any combination of ranges between about0.001:1 and about 0.06:1 (for example, the comonomer:monomer ratio is ina range from about 0.001:1 to about 0.01:1, or from about 0.04:1 toabout 0.06:1). Likewise, all other ranges disclosed herein should beinterpreted in a manner similar to these two examples.

Applicants reserve the right to proviso out or exclude any individualmembers of any such group, including any sub-ranges or combinations ofsub-ranges within the group, that can be claimed according to a range orin any similar manner, if for any reason Applicants choose to claim lessthan the full measure of the disclosure, for example, to account for areference that Applicants may be unaware of at the time of the filing ofthe application. Further, Applicants reserve the right to proviso out orexclude any individual substituents, analogs, compounds, ligands,structures, or groups thereof, or any members of a claimed group, if forany reason Applicants choose to claim less than the full measure of thedisclosure, for example, to account for a reference that Applicants maybe unaware of at the time of the filing of the application.

The terms “a,” “an,” “the,” etc., are intended to include pluralalternatives, e.g., at least one, unless otherwise specified. Forinstance, the disclosure of “an activator-support” or “anansa-metallocene compound” is meant to encompass one, or mixtures orcombinations of more than one, activator-support or ansa-metallocenecompound, respectively.

While compositions and methods are described in terms of “comprising”various components or steps, the compositions and methods can also“consist essentially of” or “consist of” the various components orsteps. For example, a catalyst composition of the present invention cancomprise; alternatively, can consist essentially of; or alternatively,can consist of; (i) an ansa-metallocene compound and (ii) an activator.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed generally to catalyst compositions,methods for preparing catalyst compositions, methods for using thecatalyst compositions to polymerize olefins, the polymer resins producedusing such catalyst compositions, and articles produced using thesepolymer resins. In one aspect, the present invention relates to acatalyst composition, said catalyst composition comprising (orconsisting essentially of, or consisting of) an ansa-metallocenecompound and an activator-support.

In another aspect, an olefin polymerization process is provided and, inthis aspect, the process comprises (or consists essentially of, orconsists of) contacting a catalyst composition with an olefin monomerand optionally an olefin comonomer under polymerization conditions toproduce an olefin polymer, wherein the catalyst composition comprises(or consists essentially of, or consists of) an ansa-metallocenecompound and an activator.

Olefin homopolymers, copolymers, terpolymers, and the like, can beproduced using the catalyst compositions and methods for olefinpolymerization disclosed herein.

Ansa-Metallocene Compound

A catalyst composition of the present invention can comprise anactivator or activator-support and an ansa-metallocene compound havingformula (I). Formula (I) is:E(Cp^(A)R^(A) _(m))(Cp^(B)R^(B) _(n))MX_(q);wherein:

M is Ti, Zr, Hf, Cr, Sc, Y, La, or a lanthanide;

Cp^(A) and Cp^(B) independently are a cyclopentadienyl, indenyl, orfluorenyl group;

each R^(A) and R^(B) independently is H or a hydrocarbyl,hydrocarbylsilyl, hydrocarbylamino, or hydrocarbyloxide group having upto 18 carbon atoms;

E is a bridging chain of 3 to 8 carbon atoms or 2 to 8 silicon,germanium, or tin atoms, wherein any substituents on atoms of thebridging chain independently are H or a hydrocarbyl group having up to18 carbon atoms;

each X independently is F; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄;OBR₂ or SO₃R, wherein R is an alkyl or aryl group having up to 18 carbonatoms; or a hydrocarbyloxide group, a hydrocarbylamino group, or ahydrocarbylsilyl group, any of which having up to 18 carbon atoms;

m is 0, 1, 2, 3, or 4;

n is 0, 1, 2, 3, or 4;

q is 2 when M is Ti, Zr, or Hf; and

q is 1 when M is Cr, Sc, Y, La, or a lanthanide.

Unless otherwise specified, formula (I) above, any other structuralformulas disclosed herein, and any metallocene species or compounddisclosed herein are not designed to show stereochemistry or isomericpositioning of the different moieties (e.g., these formulas are notintended to display cis or trans isomers, or R or S diastereoisomers),although such compounds are contemplated and encompassed by theseformulas and/or structures.

Hydrocarbyl is used herein to specify a hydrocarbon radical group thatincludes, but is not limited to, aryl, alkyl, cycloalkyl, alkenyl,cycloalkenyl, cycloalkadienyl, alkynyl, aralkyl, aralkenyl, aralkynyl,and the like, and includes all substituted, unsubstituted, linear,and/or branched derivatives thereof. Unless otherwise specified, thehydrocarbyl groups of this invention typically comprise up to about 18carbon atoms. In another aspect, hydrocarbyl groups can have up to 12carbon atoms, for instance, up to 10 carbon atoms, up to 8 carbon atoms,or up to 6 carbon atoms. A hydrocarbyloxide group, therefore, is usedgenerically to include alkoxide, aryloxide, and -(alkyl oraryl)-O-(alkyl or aryl) groups, and these groups can comprise up toabout 18 carbon atoms. Illustrative and non-limiting examples ofalkoxide and aryloxide groups (i.e., hydrocarbyloxide groups) includemethoxy, ethoxy, propoxy, butoxy, phenoxy, substituted phenoxy, and thelike. The term hydrocarbylamino group is used generically to refercollectively to alkylamino, arylamino, dialkylamino, diarylamino, and-(alkyl or aryl)-N-(alkyl or aryl) groups, and the like. Unlessotherwise specified, the hydrocarbylamino groups of this inventioncomprise up to about 18 carbon atoms. Hydrocarbylsilyl groups include,but are not limited to, alkylsilyl groups, alkenylsilyl groups,arylsilyl groups, arylalkylsilyl groups, and the like, which have up toabout 18 carbon atoms. For example, illustrative hydrocarbylsilyl groupscan include trimethylsilyl and phenyloctylsilyl. These hydrocarbyloxide,hydrocarbylamino, and hydrocarbylsilyl groups can have up to 12 carbonatoms; alternatively, up to 10 carbon atoms; or alternatively, up to 8carbon atoms, in other aspects of the present invention.

Unless otherwise specified, alkyl groups and alkenyl groups describedherein are intended to include all structural isomers, linear orbranched, of a given moiety; for example, all enantiomers and alldiastereomers are included within this definition. As an example, unlessotherwise specified, the term propyl is meant to include n-propyl andiso-propyl, while the term butyl is meant to include n-butyl, iso-butyl,t-butyl, sec-butyl, and so forth. For instance, non-limiting examples ofoctyl isomers include 2-ethyl hexyl and neooctyl. Suitable examples ofalkyl groups which can be employed in the present invention include, butare not limited to, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl,octyl, nonyl, decyl, and the like. Illustrative examples of alkenylgroups within the scope of the present invention include, but are notlimited to, ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl,octenyl, nonenyl, decenyl, and the like. The alkenyl group can be aterminal alkenyl group, but this is not a requirement. For instance,specific alkenyl group substituents can include, but are not limited to,3-butenyl, 4-pentenyl, 5-hexenyl, 6-heptenyl, 7-octenyl,3-methyl-3-butenyl, 4-methyl-3-pentenyl, 1,1-dimethyl-3-butenyl,1,1-dimethyl-4-pentenyl, and the like.

In this disclosure, aryl is meant to include aryl and arylalkyl groups,and these include, but are not limited to, phenyl, alkyl-substitutedphenyl, naphthyl, alkyl-substituted naphthyl, phenyl-substituted alkyl,naphthyl-substituted alkyl, and the like. Hence, non-limiting examplesof such “aryl” moieties that can be used in the present inventioninclude phenyl, tolyl, benzyl, dimethylphenyl, trimethylphenyl,phenylethyl, phenylpropyl, phenylbutyl, propyl-2-phenylethyl, and thelike. Unless otherwise specified, any substituted aryl moiety usedherein is meant to include all regioisomers; for example, the term tolylis meant to include any possible substituent position, that is, ortho,meta, or para.

In formula (I), M is Ti, Zr, Hf, Cr, Sc, Y, La, or a lanthanide. In oneaspect of this invention, M is Ti, Zr, Hf, or Cr. In another aspect, Mis Sc, Y, or La. In still another aspect, M is a lanthanide. Yet, insome aspects disclosed herein, M is Ti, Zr, Hf, Cr, or a lanthanide;alternatively, M is Ti or Cr; alternatively, M is Ti, Zr, or Hf;alternatively, M is Ti; alternatively, M is Zr; or alternatively, M isHf.

When M is Ti, Zr, or Hf, q is 2. However, when M is Cr, Sc, Y, La, or alanthanide, q is 1.

Cp^(A) and Cp^(B) in formula (I) independently can be acyclopentadienyl, indenyl, or fluorenyl group. In one aspect of thisinvention, at least one of Cp^(A) and Cp^(B) is a cyclopentadienylgroup. In another aspect, at least one of Cp^(A) and Cp^(B) is anindenyl group. In yet another aspect, at least one of Cp^(A) and Cp^(B)is a fluorenyl group. In still another aspect, Cp^(A) and Cp^(B)independently are a cyclopentadienyl or indenyl group. For instance,Cp^(A) can be a cyclopentadienyl group and Cp^(B) can be an indenylgroup, or both Cp^(A) and Cp^(B) can be an indenyl group.

In formula (I), each R^(A) and R^(B) independently can be H or ahydrocarbyl, hydrocarbylsilyl, hydrocarbylamino, or hydrocarbyloxidegroup having up to 18 carbon atoms or, alternatively, up to 12 carbonatoms. In some aspects, each R^(A) and R^(B) independently can be H oran alkyl group, an alkenyl group (e.g., a terminal alkenyl group), or anaryl group having up to 12 carbon atoms; alternatively, having up to 10carbon atoms; or alternatively, having up to 8 carbon atoms.Accordingly, each R^(A) and R^(B) independently can be H, methyl, ethyl,propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, ethenyl,propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl,decenyl, phenyl, tolyl, or benzyl.

Each R^(A) and R^(B) substituent, independently, can be different. Forexample, Cp^(A) can have both a methyl substituent and a propenylsubstituent. As another example, Cp^(B) can have two t-butylsubstituents. Hence, a Cp^(A)R^(A) ₂ group can be an indenyl group witha both a methyl substituent and a propenyl substituent, while aCp^(B)R^(B) ₂ group can be a fluorenyl group with two t-butylsubstituents.

In formula (I), m can be 0, 1, 2, 3, or 4, while independently n can be0, 1, 2, 3, or 4. The integers m and n reflect the total number ofsubstituents on Cp^(A) and Cp^(B), respectively (excluding bridginggroup E, to be discussed further below), irrespective of whether thesubstituents are the same or different. When m is equal to 0, Cp^(A) canbe, for example, an unsubstituted cyclopentadienyl group or anunsubstituted indenyl group, i.e., no substitutions other than bridginggroup E.

Each X independently can be F; Cl; Br; I; methyl; benzyl; phenyl; H;BH₄; OBR₂ or SO₃R, wherein R is an alkyl or aryl group; or ahydrocarbyloxide group, a hydrocarbylamino group, or a hydrocarbylsilylgroup. The hydrocarbyloxide group, the hydrocarbylamino group, thehydrocarbylsilyl group and R can have up to 18 carbon atoms or,alternatively, up to 12 carbon atoms. It is contemplated that each Xindependently can be F, Cl, Br, I, benzyl, phenyl, or methyl. Forexample, each X independently can be Cl, benzyl, phenyl, or methyl inone aspect of this invention. In another aspect, each X independentlycan be benzyl, phenyl, or methyl. Yet, in another aspect, each X can beCl; alternatively, each X can be benzyl; alternatively, each X can bephenyl; or alternatively, each X can be methyl.

Bridging group E can be a bridging chain of 3 to 8 carbon atoms or 2 to8 silicon, germanium, or tin atoms. For example, E can be a bridgingchain of 3 to 8 carbon atoms, of 3 to 6 carbon atoms, of 3 to 4 carbonsatoms, of 3 carbon atoms, or of 4 carbons atoms. Alternatively, E can bea bridging chain of 2 to 8 silicon, germanium, or tin atoms, of 2 to 6silicon, germanium, or tin atoms, of 2 to 4 silicon, germanium, or tinatoms, of 2 to 4 silicon atoms, of 2 silicon atoms, of 3 silicon atoms,or of 4 silicon atoms.

Any substituents on atoms of the bridging chain independently are H or ahydrocarbyl group having up to 18 carbon atoms or, alternatively, havingup to 12 carbon atoms. Suitable substituents can include, but are notlimited to, H, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl,octyl, nonyl, decyl, ethenyl, propenyl, butenyl, pentenyl, hexenyl,heptenyl, octenyl, nonenyl, decenyl, phenyl, tolyl, or benzyl. In oneaspect, the substituents independently can be H, methyl, ethyl, propyl,butyl, pentyl, hexyl, allyl, butenyl, pentenyl, hexenyl, phenyl, orbenzyl. In another aspect, the substituents independently can be methyl,ethyl, propyl, butyl, allyl, butenyl, pentenyl, or phenyl.

In accordance with one aspect of this invention, E is a bridging chainhaving the formula —(CR^(10A)R^(10B))_(u)—, wherein u is an integer from3 to 8 (e.g., u is 3, 4, 5, or 6), and R^(10A) and R^(10B) areindependently H or a hydrocarbyl group having up to 18 carbon atoms;alternatively, up to 12 carbon atoms; or alternatively, up to 8 carbonatoms. It is contemplated that R^(10A) and R^(10B) independently can beH, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl,decyl, ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl,nonenyl, decenyl, phenyl, tolyl, or benzyl; alternatively, H, methyl,ethyl, propyl, butyl, allyl, butenyl, pentenyl, phenyl, or benzyl; oralternatively, H, methyl, ethyl, propyl, or butyl. In some aspects, u is3, 4, 5, or 6, and R^(10A) and R^(10B) both are H, or methyl, or ethyl,or propyl, or butyl, or allyl, or butenyl, or pentenyl, or phenyl, orbenzyl.

In accordance with another aspect of this invention, E is a bridgingchain having the formula —(SiR^(11A)R^(11B))_(v)—, wherein v is aninteger from 2 to 8 (e.g., v is 2, 3, 4, 5, or 6), and R^(11A) andR^(11B) are independently H or a hydrocarbyl group having up to 18carbon atoms; alternatively, up to 12 carbon atoms; or alternatively, upto 8 carbon atoms. It is contemplated that R^(11A) and R^(11B)independently can be H, methyl, ethyl, propyl, butyl, pentyl, hexyl,heptyl, octyl, nonyl, decyl, ethenyl, propenyl, butenyl, pentenyl,hexenyl, heptenyl, octenyl, nonenyl, decenyl, phenyl, tolyl, or benzyl;alternatively, H, methyl, ethyl, propyl, butyl, allyl, butenyl,pentenyl, phenyl, or benzyl; or alternatively, H, methyl, ethyl, propyl,or butyl. In some aspects, v is 2, 3, 4, 5, or 6 (e.g., v is 2), andR^(11A) and R^(11B) both are H, or methyl, or ethyl, or propyl, orbutyl, or allyl, or butenyl, or pentenyl, or phenyl, or benzyl.

It is contemplated in aspects of the invention that M in formula (I) canbe Ti, Zr, or Hf; q can be 2; each R^(A) and R^(B) independently can beH or a hydrocarbyl group having up to 12 carbon atoms; and E can be abridging chain of 3 to 6 carbon atoms or 2 to 4 silicon atoms, whereinany substituents on atoms of the bridging chain independently can be Hor a hydrocarbyl group having up to 12 carbon atoms. Additionally, eachX in formula (I) independently can be F, Cl, Br, I, methyl, benzyl, orphenyl; m can be 0, 1, or 2; and n can be 0, 1, or 2.

In a further aspect, M can be Zr or Hf; each R^(A) and R^(B)independently can be H, methyl, ethyl, propyl, butyl, pentyl, hexyl,heptyl, octyl, nonyl, decyl, ethenyl, propenyl, butenyl, pentenyl,hexenyl, heptenyl, octenyl, nonenyl, decenyl, phenyl, tolyl, or benzyl;E can be a bridging chain of 3 to 4 carbon atoms or 2 to 3 siliconatoms, wherein any substituents on atoms of the bridging chainindependently can be H or methyl; m can be 0 or 1; and n can be 0 or 1.Even further, Cp^(A) and Cp^(B) independently can be a cyclopentadienylgroup or an indenyl group, E can be —SiMe₂—SiMe₂—, and each X can be Cl,in other aspects of this invention.

Non-limiting examples of ansa-metallocene compounds having formula (I)that are suitable for use in catalyst compositions and polymerizationprocesses disclosed herein, either singularly or in combination,include, but are not limited to, the following compounds:

and the like, including combinations thereof.

In accordance with another aspect of this invention, theansa-metallocene compound having formula (I) can comprise (or consistessentially of, or consist of) an ansa-metallocene compound havingformula (II), or formula (III), or formula (IV), or formula (V), orformula (VI), or formula (VII), or combinations thereof:

In formulas (II), (III), (IV), (V), (VI), and (VII), X, R^(A), R^(B), m,and n are as described above for formula (I). In some aspects, forexample, each X in formulas (II), (III), (IV), (V), (VI), and (VII)independently can be F, Cl, Br, I, methyl, benzyl, or phenyl, while eachR^(A) and R^(B) independently can be H, methyl, ethyl, propyl, butyl,pentyl, hexyl, heptyl, octyl, nonyl, decyl, ethenyl, propenyl, butenyl,pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, phenyl, tolyl,or benzyl.

M can be Ti, Zr, or Hf in formulas (II), (III), (IV), (V), (VI), and(VII), while m′+m″=m and n′+n″=n. The substituents on atoms of thesilicon bridging chain, R^(E), R^(F), R^(G), and R^(H), independentlycan be H or a hydrocarbyl group having up to 18 carbon atoms or,alternatively, having up to 12 carbon atoms. Accordingly, R^(E), R^(F),R^(G), and R^(H) independently can be H, methyl, ethyl, propyl, butyl,pentyl, hexyl, heptyl, octyl, nonyl, decyl, ethenyl, propenyl, butenyl,pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, phenyl, tolyl,or benzyl; alternatively, R^(E), R^(F), R^(G), and R^(H) independentlycan be H, methyl, ethyl, propyl, butyl, pentyl, hexyl, allyl, butenyl,pentenyl, hexenyl, phenyl, or benzyl; alternatively, R^(E), R^(F),R^(G), and R^(H) independently can be methyl, ethyl, propyl, butyl,allyl, butenyl, pentenyl, or phenyl; alternatively, R^(E), R^(F), R^(G),and R^(H) can be H; alternatively, R^(E), R^(F), R^(G), and R^(H) can bemethyl; alternatively, R^(E), R^(F), R^(G), and R^(H) can be ethyl;alternatively, R^(E), R^(F), R^(G), and R^(H) can be propyl;alternatively, R^(E), R^(F), R^(G), and R^(H) can be butyl;alternatively, R^(E), R^(F), R^(G), and R^(H) can be allyl;alternatively, R^(E), R^(F), R^(G), and R^(H) can be butenyl;alternatively, R^(E), R^(F), R^(G), and R^(H) can be pentenyl; oralternatively, R^(E), R^(F), R^(G), and R^(H) can be phenyl.

In accordance with another aspect of this invention, theansa-metallocene compound having formula (I) can comprise (or consistessentially of, or consist of) an ansa-metallocene compound havingformula (C), formula (D), formula (E), or combinations thereof.

Formula (C) is

wherein:

M³ is Zr or Hf;

X⁴ and X⁵ are independently F; Cl; Br; I; methyl; benzyl; phenyl; H;BH₄; OBR₂ or SO₃R, wherein R is an alkyl or aryl group having up to 18carbon atoms; or a hydrocarbyloxide group, a hydrocarbylamino group, ora hydrocarbylsilyl group, any of which having up to 18 carbon atoms;

E³ is a bridging group having the formula—SiR^(7D)R^(8D)—SiR^(7E)R^(8E)—, wherein R^(7D), R^(8D), R^(7E), andR^(8E) are independently H or a hydrocarbyl group having up to 10 carbonatoms;

R⁹ and R¹⁰ are independently H or a hydrocarbyl group having up to 18carbon atoms; and

Cp¹ is a cyclopentadienyl or indenyl group, any substituent on Cp¹ is Hor a hydrocarbyl or hydrocarbylsilyl group having up to 18 carbon atoms.

In formula (C), M³ can be Zr or Hf, while X⁴ and X⁵ independently can beF; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄; OBR₂ or SO₃R, wherein Rcan be an alkyl or aryl group; or a hydrocarbyloxide group, ahydrocarbylamino group, or a hydrocarbylsilyl group. Thehydrocarbyloxide group, the hydrocarbylamino group, the hydrocarbylsilylgroup and R can have up to 18 carbon atoms or, alternatively, up to 12carbon atoms.

X⁴ and X⁵ independently can be F, Cl, Br, I, benzyl, phenyl, or methyl.For example, X⁴ and X⁵ independently are Cl, benzyl, phenyl, or methylin one aspect of this invention. In another aspect, X⁴ and X⁵independently are benzyl, phenyl, or methyl. Yet, in another aspect,both X⁴ and X⁵ can be Cl; alternatively, both X⁴ and X⁵ can be benzyl;alternatively, both X⁴ and X⁵ can be phenyl; or alternatively, both X⁴and X⁵ can be methyl.

In formula (C), E³ can be a bridging group having the formula—SiR^(7D)R^(8D)—SiR^(7E)R^(8E)—, wherein R^(7D), R^(8D), R^(7E), andR^(8E) are independently H or a hydrocarbyl group having up to 10 carbonatoms or, alternatively, up to 6 carbon atoms. Accordingly, in aspectsof this invention, R^(7D), R^(8D), R^(7E), and R^(8E) independently canbe H or an alkyl or an alkenyl group having up to 6 carbon atoms;alternatively, R^(7D), R^(8D), R^(7E), and R^(8E) independently can beH, methyl, ethyl, propyl, butyl, allyl, butenyl, or pentenyl;alternatively, R^(7D), R^(8D), R^(7E), and R^(8E) independently can beH, methyl, or ethyl; alternatively, R^(7D), R^(8D), R^(7E), and R^(8E)can be H; or alternatively, R^(7D), R^(8D), R^(7E), and R^(8E) can bemethyl.

R⁹ and R¹⁰ on the fluorenyl group in formula (C) independently can be Hor a hydrocarbyl group having up to 18 carbon atoms or, alternatively,having up to 12 carbon atoms. Accordingly, R⁹ and R¹⁰ independently canbe H or a hydrocarbyl group having up to 8 carbon atoms, such as, forexample, alkyl groups: methyl, ethyl, propyl, butyl, pentyl, or hexyl,and the like. In some aspects, R⁹ and R¹⁰ are independently methyl,ethyl, propyl, n-butyl, t-butyl, or hexyl, while in other aspects, R⁹and R¹⁰ are independently H or t-butyl. For example, both R⁹ and R¹⁰ canbe H or, alternatively, both R⁹ and R¹⁰ can be t-butyl.

In formula (C), Cp¹ is a cyclopentadienyl or indenyl group. Often, Cp¹is a cyclopentadienyl group. Any substituent on Cp¹ can be H or ahydrocarbyl or hydrocarbylsilyl group having up to 18 carbon atoms; oralternatively, any substituent can be H or a hydrocarbyl orhydrocarbylsilyl group having up to 12 carbon atoms. Possiblesubstituents on Cp¹ may include H, therefore this invention comprisespartially saturated ligands such as tetrahydroindenyl, partiallysaturated indenyl, and the like.

In one aspect, Cp¹ has no additional substitutions other than thoseshown in formula (C), e.g., no substituents other than the bridginggroup E³. In another aspect, Cp¹ can have one or two substituents, andeach substituent independently is H or an alkyl, alkenyl, alkylsilyl, oralkenylsilyl group having up to 8 carbon atoms, or alternatively, up to6 carbon atoms. Yet, in another aspect, Cp¹ can have a single H, methylethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, ethenyl, propenyl,butenyl, pentenyl, hexenyl, heptenyl, or octenyl substituent.

In accordance with one aspect of this invention, X⁴ and X⁵ independentlycan be F, Cl, Br, I, benzyl, phenyl, or methyl, while R⁹ and R¹⁰independently can be H or t-butyl, and Cp¹ either has no additionalsubstituents or Cp¹ can have a single substituent selected from H or analkyl, alkenyl, alkylsilyl, or alkenylsilyl group having up to 8 carbonatoms. In these and other aspects, E³ can be a bridging group having theformula —SiR^(7D)R^(8D)—SiR^(7E)R^(8E)—, wherein R^(7D), R^(8D), R^(7E),and R^(8E) are independently H or methyl.

Formula (D) is

wherein:

M⁴ is Zr or Hf;

X⁶ and X⁷ are independently F; Cl; Br; I; methyl; benzyl; phenyl; H;BH₄;

OBR₂ or SO₃R, wherein R is an alkyl or aryl group having up to 18 carbonatoms; or a hydrocarbyloxide group, a hydrocarbylamino group, or ahydrocarbylsilyl group, any of which having up to 18 carbon atoms;

E⁴ is a bridging group having the formula—SiR^(12D)R^(13D)—SiR^(12E)R^(13E)—, wherein R^(12D), R^(13D), R^(12E),and R^(13E) are independently H or a hydrocarbyl group having up to 10carbon atoms; and

R¹⁴, R¹⁵, R¹⁶, and R¹⁷ are independently H or a hydrocarbyl group havingup to 18 carbon atoms.

In formula (D), M⁴ can be Zr or Hf, while X⁶ and X⁷ independently can beF; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄; OBR₂ or SO₃R, wherein R isan alkyl or aryl group; or a hydrocarbyloxide group, a hydrocarbylaminogroup, or a hydrocarbylsilyl group. The hydrocarbyloxide group, thehydrocarbylamino group, the hydrocarbylsilyl group and R can have up to18 carbon atoms or, alternatively, up to 12 carbon atoms.

X⁶ and X⁷ independently can be F, Cl, Br, I, benzyl, phenyl, or methyl.For example, X⁶ and X⁷ independently are Cl, benzyl, phenyl, or methylin one aspect of this invention. In another aspect, X⁶ and X⁷independently are benzyl, phenyl, or methyl. Yet, in another aspect,both X⁶ and X⁷ can be Cl; alternatively, both X⁶ and X⁷ can be benzyl;alternatively, both X⁶ and X⁷ can be phenyl; or alternatively, both X⁶and X⁷ can be methyl.

In formula (D), E⁴ can be a bridging group having the formula—SiR^(12D)R^(13D)—SiR^(12E)R^(13E)—, wherein R^(12D), R^(13D), R^(12E),and R^(13E) independently can be H or a hydrocarbyl group having up to10 carbon atoms or, alternatively, up to 6 carbon atoms. Accordingly, inaspects of this invention, R^(12D), R^(13D), R^(12E), and R^(13E)independently can be H or an alkyl or an alkenyl group having up to 6carbon atoms; alternatively, R^(12D), R^(13D), R^(12E), and R^(13E)independently can be H, methyl, ethyl, propyl, butyl, allyl, butenyl, orpentenyl; alternatively, R^(12D), R^(13D), R^(12E), and R^(13E)independently can be H, methyl, ethyl, propyl, or butyl; alternatively,R^(12D), R^(13D), R^(12E), and R^(13E) independently can be H, methyl,or ethyl; alternatively, R^(12D), R^(13D), R^(12E), and R^(13E) can beH; or alternatively, R^(12D), R^(13D), R^(12E), and R^(13E) can bemethyl.

R¹⁴, R¹⁵, R¹⁶, and R¹⁷ on the fluorenyl groups in formula (D)independently can be H or a hydrocarbyl group having up to 18 carbonatoms or, alternatively, having up to 12 carbon atoms. Accordingly, R¹⁴,R¹⁵, R¹⁶, and R¹⁷ independently can be H or a hydrocarbyl group havingup to 8 carbon atoms, such as, for example, alkyl groups: methyl, ethyl,propyl, butyl, pentyl, or hexyl, and the like. In some aspects, R¹⁴,R¹⁵, R¹⁶, and R¹⁷ are independently methyl, ethyl, propyl, n-butyl,t-butyl, or hexyl, while in other aspects, R¹⁴, R¹⁵, R¹⁶, and R¹⁷ areindependently H or t-butyl. For example, R¹⁴, R¹⁵, R¹⁶, and R¹⁷ can be Hor, alternatively, R¹⁴, R¹⁵, R¹⁶, and R¹⁷ can be t-butyl.

It is contemplated that X⁶ and X⁷ independently can be F, Cl, Br, I,benzyl, phenyl, or methyl in formula (D), and R¹⁴, R¹⁵, R¹⁶, and R¹⁷independently can be H or t-butyl. In these and other aspects, E⁴ can bea bridging group having the formula —SiR^(12D)R^(13D)—SiR^(12E)R^(13E)—,wherein R^(12D), R^(13D), R^(12E), and R^(13E) are independently H ormethyl.

Formula (E) is

wherein:

M⁵ is Zr or Hf;

X⁸ and X⁹ are independently F; Cl; Br; I; methyl; benzyl; phenyl; H;BH₄; OBR₂ or SO₃R, wherein R is an alkyl or aryl group having up to 18carbon atoms; or a hydrocarbyloxide group, a hydrocarbylamino group, ora hydrocarbylsilyl group, any of which having up to 18 carbon atoms; and

E⁵ is a bridging group selected from:

-   -   a bridging group having the formula —(CH₂)_(w)—, wherein w is an        integer from 3 to 8, inclusive, or    -   a bridging group having the formula        —SiR^(20B)R^(21B)—SiR^(20C)R^(21C)—, wherein R^(20B), R^(21B),        R^(20C), and R^(21C) are independently H or a hydrocarbyl group        having up to 10 carbon atoms.

In formula (E), M⁵ can be Zr or Hf, while X⁸ and X⁹ independently can beF; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄; OBR₂ or SO₃R, wherein R isan alkyl or aryl group; or a hydrocarbyloxide group, a hydrocarbylaminogroup, or a hydrocarbylsilyl group. The hydrocarbyloxide group, thehydrocarbylamino group, the hydrocarbylsilyl group and R can have up to18 carbon atoms or, alternatively, up to 12 carbon atoms.

X⁸ and X⁹ independently can be F, Cl, Br, I, benzyl, phenyl, or methyl.For example, X⁸ and X⁹ independently are Cl, benzyl, phenyl, or methylin one aspect of this invention. In another aspect, X⁸ and X⁹independently are benzyl, phenyl, or methyl. Yet, in another aspect,both X⁸ and X⁹ can be Cl; alternatively, both X⁸ and X⁹ can be benzyl;alternatively, both X⁸ and X⁹ can be phenyl; or alternatively, both X⁸and X⁹ can be methyl.

In formula (E), E⁵ is a bridging group. In accordance with an aspect ofthis invention, E⁵ can be a bridging group having the formula—(CH₂)_(w)—, wherein w is an integer from 3 to 8, inclusive. The integerw can be 3, 4, 5, or 6 in some aspects of this invention. In accordancewith another aspect of this invention, E⁵ can be a bridging group havingthe formula —SiR^(20B)R^(21B)—SiR^(20C)R^(21C)—, wherein R^(20B),R^(21B), R^(20C), and R^(21C) independently can be H or a hydrocarbylgroup having up to 10 carbon atoms or, alternatively, up to 6 carbonatoms. Accordingly, in aspects of this invention, R^(2B), R^(21B),R^(20C), and R^(21C) independently can be H or an alkyl or an alkenylgroup having up to 6 carbon atoms; alternatively, R^(20B), R^(21B),R^(20C), and R^(21C) independently can be H, methyl, ethyl, propyl,butyl, allyl, butenyl, or pentenyl; alternatively, R^(20B), R^(21B),R^(20C), and R^(21C) independently can be H, methyl, ethyl, propyl, orbutyl; alternatively, R^(2B), R^(21B), R^(20C), and R^(21C)independently can be H, methyl, or ethyl; alternatively, R^(20B),R^(21B), R^(20C), and R^(21C) can be H; or alternatively, R^(20B),R^(21B), R^(20C), and R^(21C) can be methyl.

In an aspect of this invention, X⁸ and X⁹ in formula (E) independentlycan be F, Cl, Br, I, benzyl, phenyl, or methyl, and in some aspects, E⁵can be a bridging group having the formula —(CH₂)_(w)—, wherein w isequal to 3, 4, or 5, or alternatively, E⁵ can be a bridging group havingthe formula —SiR^(20B)R^(21B)—SiR^(20C)R^(21C)—, wherein R^(20B),R^(21B), R^(20C), and R^(21C) are independently H or methyl.

Non-limiting examples of ansa-metallocene compounds having formula (E)that are suitable for use herein include, but are not limited to, thefollowing:

and the like, or combinations thereof.

As noted above, unless otherwise specified, formulas (C), (D), and (E),or any other structural formulas disclosed herein, and any metallocenespecies disclosed herein are not designed to show stereochemistry orisomeric positioning of the different moieties (e.g., these formulas arenot intended to display cis or trans isomers, or R or Sdiastereoisomers), although such compounds are contemplated andencompassed by these formulas and/or structures.

Activator-Support

The present invention encompasses various catalyst compositionscontaining an activator, which can be an activator-support. In oneaspect, the activator-support comprises a chemically-treated solidoxide. Alternatively, the activator-support can comprise a clay mineral,a pillared clay, an exfoliated clay, an exfoliated clay gelled intoanother oxide matrix, a layered silicate mineral, a non-layered silicatemineral, a layered aluminosilicate mineral, a non-layeredaluminosilicate mineral, or any combination thereof.

Generally, chemically-treated solid oxides exhibit enhanced acidity ascompared to the corresponding untreated solid oxide compound. Thechemically-treated solid oxide also functions as a catalyst activator ascompared to the corresponding untreated solid oxide. While thechemically-treated solid oxide activates the metallocene in the absenceof co-catalysts, it is not necessary to eliminate co-catalysts from thecatalyst composition. The activation function of the activator-supportis evident in the enhanced activity of catalyst composition as a whole,as compared to a catalyst composition containing the correspondinguntreated solid oxide. However, it is believed that thechemically-treated solid oxide can function as an activator, even in theabsence of an organoaluminum compound, aluminoxanes, organoboron ororganoborate compounds, ionizing ionic compounds, and the like.

The chemically-treated solid oxide can comprise a solid oxide treatedwith an electron-withdrawing anion. While not intending to be bound bythe following statement, it is believed that treatment of the solidoxide with an electron-withdrawing component augments or enhances theacidity of the oxide. Thus, either the activator-support exhibits Lewisor Brønsted acidity that is typically greater than the Lewis or Brønstedacid strength of the untreated solid oxide, or the activator-support hasa greater number of acid sites than the untreated solid oxide, or both.One method to quantify the acidity of the chemically-treated anduntreated solid oxide materials is by comparing the polymerizationactivities of the treated and untreated oxides under acid catalyzedreactions.

Chemically-treated solid oxides of this invention are formed generallyfrom an inorganic solid oxide that exhibits Lewis acidic or Brønstedacidic behavior and has a relatively high porosity. The solid oxide ischemically-treated with an electron-withdrawing component, typically anelectron-withdrawing anion, to form an activator-support.

According to one aspect of the present invention, the solid oxide usedto prepare the chemically-treated solid oxide has a pore volume greaterthan about 0.1 cc/g. According to another aspect of the presentinvention, the solid oxide has a pore volume greater than about 0.5cc/g. According to yet another aspect of the present invention, thesolid oxide has a pore volume greater than about 1.0 cc/g.

In another aspect, the solid oxide has a surface area of from about 100to about 1000 m²/g. In yet another aspect, the solid oxide has a surfacearea of from about 200 to about 800 m²/g. In still another aspect of thepresent invention, the solid oxide has a surface area of from about 250to about 600 m²/g.

The chemically-treated solid oxide can comprise a solid inorganic oxidecomprising oxygen and one or more elements selected from Group 2, 3, 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 of the periodic table, orcomprising oxygen and one or more elements selected from the lanthanideor actinide elements (See: Hawley's Condensed Chemical Dictionary,11^(th) Ed., John Wiley & Sons, 1995; Cotton, F. A., Wilkinson, G.,Murillo, C. A., and Bochmann, M., Advanced Inorganic Chemistry, 6^(th)Ed., Wiley-Interscience, 1999). For example, the inorganic oxide cancomprise oxygen and an element, or elements, selected from Al, B, Be,Bi, Cd, Co, Cr, Cu, Fe, Ga, La, Mn, Mo, Ni, Sb, Si, Sn, Sr, Th, Ti, V,W, P, Y, Zn, and Zr.

Suitable examples of solid oxide materials or compounds that can be usedto form the chemically-treated solid oxide include, but are not limitedto, Al₂O₃, B₂O₃, BeO, Bi₂O₃, CdO, Co₃O₄, Cr₂O₃, CuO, Fe₂O₃, Ga₂O₃,La₂O₃, Mn₂O₃, MoO₃, NiO, P₂O₅, Sb₂O₅, SiO₂, SnO₂, SrO, ThO₂, TiO₂, V₂O₅,WO₃, Y₂O₃, ZnO, ZrO₂, and the like, including mixed oxides thereof, andcombinations thereof. For example, the solid oxide can comprise silica,alumina, silica-alumina, silica-coated alumina, aluminum phosphate,aluminophosphate, heteropolytungstate, titania, zirconia, magnesia,boria, zinc oxide, mixed oxides thereof, or any combination thereof.

The solid oxide of this invention encompasses oxide materials such asalumina, “mixed oxide” compounds thereof such as silica-alumina, andcombinations and mixtures thereof. The mixed oxide compounds such assilica-alumina can be single or multiple chemical phases with more thanone metal combined with oxygen to form a solid oxide compound. Examplesof mixed oxides that can be used in the activator-support of the presentinvention include, but are not limited to, silica-alumina,silica-titania, silica-zirconia, zeolites, various clay minerals,alumina-titania, alumina-zirconia, zinc-aluminate, alumina-boria,silica-boria, aluminophosphate-silica, titania-zirconia, and the like.The solid oxide of this invention also encompasses oxide materials suchas silica-coated alumina, as described in U.S. Patent Publication No.2010-0076167, the disclosure of which is incorporated herein byreference in its entirety.

The electron-withdrawing component used to treat the solid oxide can beany component that increases the Lewis or Brønsted acidity of the solidoxide upon treatment (as compared to the solid oxide that is not treatedwith at least one electron-withdrawing anion). According to one aspectof the present invention, the electron-withdrawing component is anelectron-withdrawing anion derived from a salt, an acid, or othercompound, such as a volatile organic compound, that serves as a sourceor precursor for that anion. Examples of electron-withdrawing anionsinclude, but are not limited to, sulfate, bisulfate, fluoride, chloride,bromide, iodide, fluorosulfate, fluoroborate, phosphate,fluorophosphate, trifluoroacetate, triflate, fluorozirconate,fluorotitanate, phospho-tungstate, and the like, including mixtures andcombinations thereof. In addition, other ionic or non-ionic compoundsthat serve as sources for these electron-withdrawing anions also can beemployed in the present invention. It is contemplated that theelectron-withdrawing anion can be, or can comprise, fluoride, chloride,bromide, phosphate, triflate, bisulfate, or sulfate, and the like, orany combination thereof, in some aspects of this invention. In otheraspects, the electron-withdrawing anion can comprise sulfate, bisulfate,fluoride, chloride, bromide, iodide, fluorosulfate, fluoroborate,phosphate, fluorophosphate, trifluoroacetate, triflate, fluorozirconate,fluorotitanate, and the like, or any combination thereof.

Thus, for example, the activator-support (e.g., chemically-treated solidoxide) used in the catalyst compositions of the present invention canbe, or can comprise, fluorided alumina, chlorided alumina, bromidedalumina, sulfated alumina, fluorided silica-alumina, chloridedsilica-alumina, bromided silica-alumina, sulfated silica-alumina,fluorided silica-zirconia, chlorided silica-zirconia, bromidedsilica-zirconia, sulfated silica-zirconia, fluorided silica-titania,fluorided silica-coated alumina, sulfated silica-coated alumina,phosphated silica-coated alumina, and the like, or combinations thereof.In one aspect, the activator-support can be, or can comprise, fluoridedalumina, sulfated alumina, fluorided silica-alumina, sulfatedsilica-alumina, fluorided silica-coated alumina, sulfated silica-coatedalumina, phosphated silica-coated alumina, and the like, or anycombination thereof. In another aspect, the activator-support comprisesfluorided alumina; alternatively, comprises chlorided alumina;alternatively, comprises sulfated alumina; alternatively, comprisesfluorided silica-alumina; alternatively, comprises sulfatedsilica-alumina; alternatively, comprises fluorided silica-zirconia;alternatively, comprises chlorided silica-zirconia; or alternatively,comprises fluorided silica-coated alumina.

When the electron-withdrawing component comprises a salt of anelectron-withdrawing anion, the counterion or cation of that salt can beselected from any cation that allows the salt to revert or decomposeback to the acid during calcining. Factors that dictate the suitabilityof the particular salt to serve as a source for the electron-withdrawinganion include, but are not limited to, the solubility of the salt in thedesired solvent, the lack of adverse reactivity of the cation,ion-pairing effects between the cation and anion, hygroscopic propertiesimparted to the salt by the cation, and the like, and thermal stabilityof the anion. Examples of suitable cations in the salt of theelectron-withdrawing anion include, but are not limited to, ammonium,trialkyl ammonium, tetraalkyl ammonium, tetraalkyl phosphonium, H⁺,[H(OEt₂)₂]⁺, and the like.

Further, combinations of one or more different electron-withdrawinganions, in varying proportions, can be used to tailor the specificacidity of the activator-support to the desired level. Combinations ofelectron-withdrawing components can be contacted with the oxide materialsimultaneously or individually, and in any order that affords thedesired chemically-treated solid oxide acidity. For example, one aspectof this invention is employing two or more electron-withdrawing anionsource compounds in two or more separate contacting steps.

Thus, one example of such a process by which a chemically-treated solidoxide is prepared is as follows: a selected solid oxide, or combinationof solid oxides, is contacted with a first electron-withdrawing anionsource compound to form a first mixture; this first mixture is calcinedand then contacted with a second electron-withdrawing anion sourcecompound to form a second mixture; the second mixture is then calcinedto form a treated solid oxide. In such a process, the first and secondelectron-withdrawing anion source compounds can be either the same ordifferent compounds.

According to another aspect of the present invention, thechemically-treated solid oxide comprises a solid inorganic oxidematerial, a mixed oxide material, or a combination of inorganic oxidematerials, that is chemically-treated with an electron-withdrawingcomponent, and optionally treated with a metal source, including metalsalts, metal ions, or other metal-containing compounds. Non-limitingexamples of the metal or metal ion include zinc, nickel, vanadium,titanium, silver, copper, gallium, tin, tungsten, molybdenum, zirconium,and the like, or combinations thereof. Examples of chemically-treatedsolid oxides that contain a metal or metal ion include, but are notlimited to, chlorided zinc-impregnated alumina, fluoridedtitanium-impregnated alumina, fluorided zinc-impregnated alumina,chlorided zinc-impregnated silica-alumina, fluorided zinc-impregnatedsilica-alumina, sulfated zinc-impregnated alumina, chlorided zincaluminate, fluorided zinc aluminate, sulfated zinc aluminate,silica-coated alumina treated with hexafluorotitanic acid, silica-coatedalumina treated with zinc and then fluorided, and the like, or anycombination thereof.

Any method of impregnating the solid oxide material with a metal can beused. The method by which the oxide is contacted with a metal source,typically a salt or metal-containing compound, can include, but is notlimited to, gelling, co-gelling, impregnation of one compound ontoanother, and the like. If desired, the metal-containing compound isadded to or impregnated into the solid oxide in solution form, andsubsequently converted into the supported metal upon calcining.Accordingly, the solid inorganic oxide can further comprise a metalselected from zinc, titanium, nickel, vanadium, silver, copper, gallium,tin, tungsten, molybdenum, and the like, or combinations of thesemetals. For example, zinc is often used to impregnate the solid oxidebecause it can provide improved catalyst activity at a low cost.

The solid oxide can be treated with metal salts or metal-containingcompounds before, after, or at the same time that the solid oxide istreated with the electron-withdrawing anion. Following any contactingmethod, the contacted mixture of solid compound, electron-withdrawinganion, and the metal ion is typically calcined. Alternatively, a solidoxide material, an electron-withdrawing anion source, and the metal saltor metal-containing compound are contacted and calcined simultaneously.

Various processes are used to form the chemically-treated solid oxideuseful in the present invention. The chemically-treated solid oxide cancomprise the contact product of one or more solid oxides with one ormore electron-withdrawing anion sources. It is not required that thesolid oxide be calcined prior to contacting the electron-withdrawinganion source. The contact product typically is calcined either during orafter the solid oxide is contacted with the electron-withdrawing anionsource. The solid oxide can be calcined or uncalcined. Various processesto prepare solid oxide activator-supports that can be employed in thisinvention have been reported. For example, such methods are described inU.S. Pat. Nos. 6,107,230, 6,165,929, 6,294,494, 6,300,271, 6,316,553,6,355,594, 6,376,415, 6,388,017, 6,391,816, 6,395,666, 6,524,987,6,548,441, 6,548,442, 6,576,583, 6,613,712, 6,632,894, 6,667,274, and6,750,302, the disclosures of which are incorporated herein by referencein their entirety.

According to one aspect of the present invention, the solid oxidematerial is chemically-treated by contacting it with anelectron-withdrawing component, typically an electron-withdrawing anionsource. Further, the solid oxide material optionally is chemicallytreated with a metal ion, and then calcined to form a metal-containingor metal-impregnated chemically-treated solid oxide. According toanother aspect of the present invention, the solid oxide material andelectron-withdrawing anion source are contacted and calcinedsimultaneously.

The method by which the oxide is contacted with the electron-withdrawingcomponent, typically a salt or an acid of an electron-withdrawing anion,can include, but is not limited to, gelling, co-gelling, impregnation ofone compound onto another, and the like. Thus, following any contactingmethod, the contacted mixture of the solid oxide, electron-withdrawinganion, and optional metal ion, is calcined.

The solid oxide activator-support (i.e., chemically-treated solid oxide)thus can be produced by a process comprising:

1) contacting a solid oxide (or solid oxides) with anelectron-withdrawing anion source compound (or compounds) to form afirst mixture; and

2) calcining the first mixture to form the solid oxideactivator-support.

According to another aspect of the present invention, the solid oxideactivator-support (chemically-treated solid oxide) is produced by aprocess comprising:

1) contacting a solid oxide (or solid oxides) with a firstelectron-withdrawing anion source compound to form a first mixture;

2) calcining the first mixture to produce a calcined first mixture;

3) contacting the calcined first mixture with a secondelectron-withdrawing anion source compound to form a second mixture; and

4) calcining the second mixture to form the solid oxideactivator-support.

According to yet another aspect of the present invention, thechemically-treated solid oxide is produced or formed by contacting thesolid oxide with the electron-withdrawing anion source compound, wherethe solid oxide compound is calcined before, during, or after contactingthe electron-withdrawing anion source, and where there is a substantialabsence of aluminoxanes, organoboron or organoborate compounds, andionizing ionic compounds.

Calcining of the treated solid oxide generally is conducted in anambient atmosphere, typically in a dry ambient atmosphere, at atemperature from about 200° C. to about 900° C., and for a time of about1 minute to about 100 hours. Calcining can be conducted at a temperatureof from about 300° C. to about 800° C., or alternatively, at atemperature of from about 400° C. to about 700° C. Calcining can beconducted for about 30 minutes to about 50 hours, or for about 1 hour toabout 15 hours. Thus, for example, calcining can be carried out forabout 1 to about 10 hours at a temperature of from about 350° C. toabout 550° C. Any suitable ambient atmosphere can be employed duringcalcining. Generally, calcining is conducted in an oxidizing atmosphere,such as air. Alternatively, an inert atmosphere, such as nitrogen orargon, or a reducing atmosphere, such as hydrogen or carbon monoxide,can be used.

According to one aspect of the present invention, the solid oxidematerial is treated with a source of halide ion, sulfate ion, or acombination of anions, optionally treated with a metal ion, and thencalcined to provide the chemically-treated solid oxide in the form of aparticulate solid. For example, the solid oxide material can be treatedwith a source of sulfate (termed a “sulfating agent”), a source ofchloride ion (termed a “chloriding agent”), a source of fluoride ion(termed a “fluoriding agent”), or a combination thereof, and calcined toprovide the solid oxide activator. Useful acidic activator-supportsinclude, but are not limited to, bromided alumina, chlorided alumina,fluorided alumina, sulfated alumina, bromided silica-alumina, chloridedsilica-alumina, fluorided silica-alumina, sulfated silica-alumina,bromided silica-zirconia, chlorided silica-zirconia, fluoridedsilica-zirconia, sulfated silica-zirconia, fluorided silica-titania,alumina treated with hexafluorotitanic acid, silica-coated aluminatreated with hexafluorotitanic acid, silica-alumina treated withhexafluorozirconic acid, silica-alumina treated with trifluoroaceticacid, fluorided boria-alumina, silica treated with tetrafluoroboricacid, alumina treated with tetrafluoroboric acid, alumina treated withhexafluorophosphoric acid, a pillared clay, such as a pillaredmontmorillonite, optionally treated with fluoride, chloride, or sulfate;phosphated alumina or other aluminophosphates optionally treated withsulfate, fluoride, or chloride; or any combination of the above.Further, any of these activator-supports optionally can be treated witha metal ion.

The chemically-treated solid oxide can comprise a fluorided solid oxidein the form of a particulate solid. The fluorided solid oxide can beformed by contacting a solid oxide with a fluoriding agent. The fluorideion can be added to the oxide by forming a slurry of the oxide in asuitable solvent such as alcohol or water including, but not limited to,the one to three carbon alcohols because of their volatility and lowsurface tension. Examples of suitable fluoriding agents include, but arenot limited to, hydrofluoric acid (HF), ammonium fluoride (NH₄F),ammonium bifluoride (NH₄HF₂), ammonium tetrafluoroborate (NH₄BF₄),ammonium silicofluoride (hexafluorosilicate) ((NH₄)₂SiF₆), ammoniumhexafluorophosphate (NH₄PF₆), hexafluorotitanic acid (H₂TiF₆), ammoniumhexafluorotitanic acid ((NH₄)₂TiF₆), hexafluorozirconic acid (H₂ZrF₆),AlF₃, NH₄AlF₄, analogs thereof, and combinations thereof. Triflic acidand ammonium triflate also can be employed. For example, ammoniumbifluoride (NH₄HF₂) can be used as the fluoriding agent, due to its easeof use and availability.

If desired, the solid oxide is treated with a fluoriding agent duringthe calcining step. Any fluoriding agent capable of thoroughlycontacting the solid oxide during the calcining step can be used. Forexample, in addition to those fluoriding agents described previously,volatile organic fluoriding agents can be used. Examples of volatileorganic fluoriding agents useful in this aspect of the inventioninclude, but are not limited to, freons, perfluorohexane,perfluorobenzene, fluoromethane, trifluoroethanol, and the like, andcombinations thereof. Calcining temperatures generally must be highenough to decompose the compound and release fluoride. Gaseous hydrogenfluoride (HF) or fluorine (F₂) itself also can be used with the solidoxide if fluorided while calcining. Silicon tetrafluoride (SiF₄) andcompounds containing tetrafluoroborate (BF₄) also can be employed. Oneconvenient method of contacting the solid oxide with the fluoridingagent is to vaporize a fluoriding agent into a gas stream used tofluidize the solid oxide during calcination.

Similarly, in another aspect of this invention, the chemically-treatedsolid oxide comprises a chlorided solid oxide in the form of aparticulate solid. The chlorided solid oxide is formed by contacting asolid oxide with a chloriding agent. The chloride ion can be added tothe oxide by forming a slurry of the oxide in a suitable solvent. Thesolid oxide can be treated with a chloriding agent during the calciningstep. Any chloriding agent capable of serving as a source of chlorideand thoroughly contacting the oxide during the calcining step can beused, such as SiCl₄, SiMe₂Cl₂, TiCl₄, BCl₃, and the like, includingmixtures thereof. Volatile organic chloriding agents can be used.Examples of suitable volatile organic chloriding agents include, but arenot limited to, certain freons, perchlorobenzene, chloromethane,dichloromethane, chloroform, carbon tetrachloride, trichloroethanol, andthe like, or any combination thereof. Gaseous hydrogen chloride orchlorine itself also can be used with the solid oxide during calcining.One convenient method of contacting the oxide with the chloriding agentis to vaporize a chloriding agent into a gas stream used to fluidize thesolid oxide during calcination.

The amount of fluoride or chloride ion present before calcining thesolid oxide generally is from about 1 to about 50% by weight, where theweight percent is based on the weight of the solid oxide, for example,silica-alumina, before calcining. According to another aspect of thisinvention, the amount of fluoride or chloride ion present beforecalcining the solid oxide is from about 1 to about 25% by weight, andaccording to another aspect of this invention, from about 2 to about 20%by weight. According to yet another aspect of this invention, the amountof fluoride or chloride ion present before calcining the solid oxide isfrom about 4 to about 10% by weight. Once impregnated with halide, thehalided oxide can be dried by any suitable method including, but notlimited to, suction filtration followed by evaporation, drying undervacuum, spray drying, and the like, although it is also possible toinitiate the calcining step immediately without drying the impregnatedsolid oxide.

The silica-alumina used to prepare the treated silica-alumina typicallyhas a pore volume greater than about 0.5 cc/g. According to one aspectof the present invention, the pore volume is greater than about 0.8cc/g, and according to another aspect of the present invention, greaterthan about 1.0 cc/g. Further, the silica-alumina generally has a surfacearea greater than about 100 m²/g. According to another aspect of thisinvention, the surface area is greater than about 250 m²/g. Yet, inanother aspect, the surface area is greater than about 350 m²/g.

The silica-alumina utilized in the present invention typically has analumina content from about 5 to about 95% by weight. According to oneaspect of this invention, the alumina content of the silica-alumina isfrom about 5 to about 50%, or from about 8% to about 30%, alumina byweight. In another aspect, high alumina content silica-alumina compoundscan employed, in which the alumina content of these silica-aluminacompounds typically ranges from about 60% to about 90%, or from about65% to about 80%, alumina by weight. According to yet another aspect ofthis invention, the solid oxide component comprises alumina withoutsilica, and according to another aspect of this invention, the solidoxide component comprises silica without alumina.

The sulfated solid oxide comprises sulfate and a solid oxide component,such as alumina or silica-alumina, in the form of a particulate solid.Optionally, the sulfated oxide is treated further with a metal ion suchthat the calcined sulfated oxide comprises a metal. According to oneaspect of the present invention, the sulfated solid oxide comprisessulfate and alumina. In some instances, the sulfated alumina is formedby a process wherein the alumina is treated with a sulfate source, forexample, sulfuric acid or a sulfate salt such as ammonium sulfate. Thisprocess is generally performed by forming a slurry of the alumina in asuitable solvent, such as alcohol or water, in which the desiredconcentration of the sulfating agent has been added. Suitable organicsolvents include, but are not limited to, the one to three carbonalcohols because of their volatility and low surface tension.

According to one aspect of this invention, the amount of sulfate ionpresent before calcining is from about 0.5 to about 100 parts by weightsulfate ion to about 100 parts by weight solid oxide. According toanother aspect of this invention, the amount of sulfate ion presentbefore calcining is from about 1 to about 50 parts by weight sulfate ionto about 100 parts by weight solid oxide, and according to still anotheraspect of this invention, from about 5 to about 30 parts by weightsulfate ion to about 100 parts by weight solid oxide. These weightratios are based on the weight of the solid oxide before calcining. Onceimpregnated with sulfate, the sulfated oxide can be dried by anysuitable method including, but not limited to, suction filtrationfollowed by evaporation, drying under vacuum, spray drying, and thelike, although it is also possible to initiate the calcining stepimmediately.

According to another aspect of the present invention, theactivator-support used in preparing the catalyst compositions of thisinvention comprises an ion-exchangeable activator-support, including butnot limited to silicate and aluminosilicate compounds or minerals,either with layered or non-layered structures, and combinations thereof.In another aspect of this invention, ion-exchangeable, layeredaluminosilicates such as pillared clays are used as activator-supports.When the acidic activator-support comprises an ion-exchangeableactivator-support, it can optionally be treated with at least oneelectron-withdrawing anion such as those disclosed herein, thoughtypically the ion-exchangeable activator-support is not treated with anelectron-withdrawing anion.

According to another aspect of the present invention, theactivator-support of this invention comprises clay minerals havingexchangeable cations and layers capable of expanding. Typical claymineral activator-supports include, but are not limited to,ion-exchangeable, layered aluminosilicates such as pillared clays.Although the term “support” is used, it is not meant to be construed asan inert component of the catalyst composition, but rather is to beconsidered an active part of the catalyst composition, because of itsintimate association with the metallocene component.

According to another aspect of the present invention, the clay materialsof this invention encompass materials either in their natural state orthat have been treated with various ions by wetting, ion exchange, orpillaring. Typically, the clay material activator-support of thisinvention comprises clays that have been ion exchanged with largecations, including polynuclear, highly charged metal complex cations.However, the clay material activator-supports of this invention alsoencompass clays that have been ion exchanged with simple salts,including, but not limited to, salts of Al(III), Fe(II), Fe(III), andZn(II) with ligands such as halide, acetate, sulfate, nitrate, ornitrite.

According to another aspect of the present invention, theactivator-support comprises a pillared clay. The term “pillared clay” isused to refer to clay materials that have been ion exchanged with large,typically polynuclear, highly charged metal complex cations. Examples ofsuch ions include, but are not limited to, Keggin ions which can havecharges such as 7+, various polyoxometallates, and other large ions.Thus, the term pillaring refers to a simple exchange reaction in whichthe exchangeable cations of a clay material are replaced with large,highly charged ions, such as Keggin ions. These polymeric cations arethen immobilized within the interlayers of the clay and when calcinedare converted to metal oxide “pillars,” effectively supporting the claylayers as column-like structures. Thus, once the clay is dried andcalcined to produce the supporting pillars between clay layers, theexpanded lattice structure is maintained and the porosity is enhanced.The resulting pores can vary in shape and size as a function of thepillaring material and the parent clay material used. Examples ofpillaring and pillared clays are found in: T. J. Pinnavaia, Science 220(4595), 365-371 (1983); J. M. Thomas, Intercalation Chemistry, (S.Whittington and A. Jacobson, eds.) Ch. 3, pp. 55-99, Academic Press,Inc., (1972); U.S. Pat. No. 4,452,910; U.S. Pat. No. 5,376,611; and U.S.Pat. No. 4,060,480; the disclosures of which are incorporated herein byreference in their entirety.

The pillaring process utilizes clay minerals having exchangeable cationsand layers capable of expanding. Any pillared clay that can enhance thepolymerization of olefins in the catalyst composition of the presentinvention can be used. Therefore, suitable clay minerals for pillaringinclude, but are not limited to, allophanes; smectites, bothdioctahedral (Al) and tri-octahedral (Mg) and derivatives thereof suchas montmorillonites (bentonites), nontronites, hectorites, or laponites;halloysites; vermiculites; micas; fluoromicas; chlorites; mixed-layerclays; the fibrous clays including but not limited to sepiolites,attapulgites, and palygorskites; a serpentine clay; illite; laponite;saponite; and any combination thereof. In one aspect, the pillared clayactivator-support comprises bentonite or montmorillonite. The principalcomponent of bentonite is montmorillonite.

The pillared clay can be pretreated if desired. For example, a pillaredbentonite is pretreated by drying at about 300° C. under an inertatmosphere, typically dry nitrogen, for about 3 hours, before beingadded to the polymerization reactor. Although an exemplary pretreatmentis described herein, it should be understood that the preheating can becarried out at many other temperatures and times, including anycombination of temperature and time steps, all of which are encompassedby this invention.

The activator-support used to prepare the catalyst compositions of thepresent invention can be combined with other inorganic supportmaterials, including, but not limited to, zeolites, inorganic oxides,phosphated inorganic oxides, and the like. In one aspect, typicalsupport materials that are used include, but are not limited to, silica,silica-alumina, alumina, titania, zirconia, magnesia, boria, thoria,aluminophosphate, aluminum phosphate, silica-titania, coprecipitatedsilica/titania, mixtures thereof, or any combination thereof.

According to another aspect of the present invention, one or more of themetallocene compounds can be precontacted with an olefin monomer and anorganoaluminum compound for a first period of time prior to contactingthis mixture with the activator-support. Once the precontacted mixtureof the metallocene compound(s), olefin monomer, and organoaluminumcompound is contacted with the activator-support, the compositionfurther comprising the activator-support is termed a “postcontacted”mixture. The postcontacted mixture can be allowed to remain in furthercontact for a second period of time prior to being charged into thereactor in which the polymerization process will be carried out.

According to yet another aspect of the present invention, one or more ofthe metallocene compounds can be precontacted with an olefin monomer andan activator-support for a first period of time prior to contacting thismixture with the organoaluminum compound. Once the precontacted mixtureof the metallocene compound(s), olefin monomer, and activator-support iscontacted with the organoaluminum compound, the composition furthercomprising the organoaluminum is termed a “postcontacted” mixture. Thepostcontacted mixture can be allowed to remain in further contact for asecond period of time prior to being introduced into the polymerizationreactor.

Organoaluminum Compounds

In some aspects, catalyst compositions of the present invention cancomprise one or more organoaluminum compounds. Such compounds caninclude, but are not limited to, compounds having the formula:(R^(C)C)₃Al;where R^(C) is an aliphatic group having from 1 to 10 carbon atoms. Forexample, R^(C) can be methyl, ethyl, propyl, butyl, hexyl, or isobutyl.

Other organoaluminum compounds which can be used in catalystcompositions disclosed herein can include, but are not limited to,compounds having the formula:Al(X^(A))_(p)(X^(B))_(3-p),where X^(A) is a hydrocarbyl; X^(B) is an alkoxide or an aryloxide, ahalide, or a hydride; and p is from 1 to 3, inclusive. Hydrocarbyl isused herein to specify a hydrocarbon radical group and includes, but isnot limited to, aryl, alkyl, cycloalkyl, alkenyl, cycloalkenyl,cycloalkadienyl, alkynyl, aralkyl, aralkenyl, aralkynyl, and the like,and includes all substituted, unsubstituted, branched, linear, and/orheteroatom substituted derivatives thereof.

In one aspect, X^(A) is a hydrocarbyl having from 1 to about 18 carbonatoms. In another aspect of the present invention, X^(A) is an alkylhaving from 1 to 10 carbon atoms. For example, X^(A) can be methyl,ethyl, propyl, n-butyl, sec-butyl, isobutyl, or hexyl, and the like, inyet another aspect of the present invention.

According to one aspect of the present invention, X^(B) is an alkoxideor an aryloxide, any one of which has from 1 to 18 carbon atoms, ahalide, or a hydride. In another aspect of the present invention, X^(B)is selected independently from fluorine and chlorine. Yet, in anotheraspect, X^(B) is chlorine.

In the formula, Al(X^(A))_(p)(X^(B))_(3-p), p is a number from 1 to 3,inclusive, and typically, p is 3. The value of p is not restricted to bean integer; therefore, this formula includes sesquihalide compounds orother organoaluminum cluster compounds.

Examples of organoaluminum compounds suitable for use in accordance withthe present invention include, but are not limited to, trialkylaluminumcompounds, dialkylaluminum halide compounds, dialkylaluminum alkoxidecompounds, dialkylaluminum hydride compounds, and combinations thereof.Specific non-limiting examples of suitable organoaluminum compoundsinclude trimethylaluminum (TMA), triethylaluminum (TEA),tri-n-propylaluminum (TNPA), tri-n-butylaluminum (TNBA),triisobutylaluminum (TIBA), tri-n-hexylaluminum, tri-n-octylaluminum,diisobutylaluminum hydride, diethylaluminum ethoxide, diethylaluminumchloride, and the like, or combinations thereof.

The present invention contemplates a method of precontacting ametallocene compound with an organoaluminum compound and an olefinmonomer to form a precontacted mixture, prior to contacting thisprecontacted mixture with an activator-support to form a catalystcomposition. When the catalyst composition is prepared in this manner,typically, though not necessarily, a portion of the organoaluminumcompound is added to the precontacted mixture and another portion of theorganoaluminum compound is added to the postcontacted mixture preparedwhen the precontacted mixture is contacted with the solid oxideactivator-support. However, the entire organoaluminum compound can beused to prepare the catalyst composition in either the precontacting orpostcontacting step. Alternatively, all the catalyst components arecontacted in a single step.

Further, more than one organoaluminum compound can be used in either theprecontacting or the postcontacting step. When an organoaluminumcompound is added in multiple steps, the amounts of organoaluminumcompound disclosed herein include the total amount of organoaluminumcompound used in both the precontacted and postcontacted mixtures, andany additional organoaluminum compound added to the polymerizationreactor. Therefore, total amounts of organoaluminum compounds aredisclosed regardless of whether a single organoaluminum compound or morethan one organoaluminum compound is used.

Aluminoxane Compounds

The present invention further provides a catalyst composition which cancomprise an aluminoxane compound. As used herein, the term “aluminoxane”refers to aluminoxane compounds, compositions, mixtures, or discretespecies, regardless of how such aluminoxanes are prepared, formed orotherwise provided. For example, a catalyst composition comprising analuminoxane compound can be prepared in which aluminoxane is provided asthe poly(hydrocarbyl aluminum oxide), or in which aluminoxane isprovided as the combination of an aluminum alkyl compound and a sourceof active protons such as water. Aluminoxanes are also referred to aspoly(hydrocarbyl aluminum oxides) or organoaluminoxanes.

The other catalyst components typically are contacted with thealuminoxane in a saturated hydrocarbon compound solvent, though anysolvent that is substantially inert to the reactants, intermediates, andproducts of the activation step can be used. The catalyst compositionformed in this manner is collected by any suitable method, for example,by filtration. Alternatively, the catalyst composition is introducedinto the polymerization reactor without being isolated.

The aluminoxane compound of this invention can be an oligomeric aluminumcompound comprising linear structures, cyclic structures, or cagestructures, or mixtures of all three. Cyclic aluminoxane compoundshaving the formula:

wherein R in this formula is a linear or branched alkyl having from 1 to10 carbon atoms, and p in this formula is an integer from 3 to 20, areencompassed by this invention. The AlRO moiety shown here alsoconstitutes the repeating unit in a linear aluminoxane. Thus, linearaluminoxanes having the formula:

wherein R in this formula is a linear or branched alkyl having from 1 to10 carbon atoms, and q in this formula is an integer from 1 to 50, arealso encompassed by this invention.

Further, aluminoxanes can have cage structures of the formula R^(t)_(5r+α)R^(b) _(r-α)Al_(4r)O_(3r), wherein R^(t) is a terminal linear orbranched alkyl group having from 1 to 10 carbon atoms; Rb is a bridginglinear or branched alkyl group having from 1 to 10 carbon atoms; r is 3or 4; and α is equal to n_(Al(3))−n_(O(2))+n_(O(4)), wherein n_(Al(3))is the number of three coordinate aluminum atoms, n_(O(2)) is the numberof two coordinate oxygen atoms, and n_(O(4)) is the number of 4coordinate oxygen atoms.

Thus, aluminoxanes which can be employed in the catalyst compositions ofthe present invention are represented generally by formulas such as(R—Al—O)_(p), R(R—Al—O)_(q)AlR₂, and the like. In these formulas, the Rgroup is typically a linear or branched C₁-C₆ alkyl, such as methyl,ethyl, propyl, butyl, pentyl, or hexyl. Examples of aluminoxanecompounds that can be used in accordance with the present inventioninclude, but are not limited to, methylaluminoxane, ethylaluminoxane,n-propylaluminoxane, iso-propylaluminoxane, n-butylaluminoxane,t-butylaluminoxane, sec-butylaluminoxane, iso-butylaluminoxane,1-pentylaluminoxane, 2-pentylaluminoxane, 3-pentylaluminoxane,isopentylaluminoxane, neopentylaluminoxane, and the like, or anycombination thereof. Methylaluminoxane, ethylaluminoxane, andiso-butylaluminoxane are prepared from trimethylaluminum,triethylaluminum, or triisobutylaluminum, respectively, and sometimesare referred to as poly(methyl aluminum oxide), poly(ethyl aluminumoxide), and poly(isobutyl aluminum oxide), respectively. It is alsowithin the scope of the invention to use an aluminoxane in combinationwith a trialkylaluminum, such as that disclosed in U.S. Pat. No.4,794,096, incorporated herein by reference in its entirety.

The present invention contemplates many values of p and q in thealuminoxane formulas (R—Al—O)_(p) and R(R—Al—O)_(q)AlR₂, respectively.In some aspects, p and q are at least 3. However, depending upon how theorganoaluminoxane is prepared, stored, and used, the value of p and qcan vary within a single sample of aluminoxane, and such combinations oforganoaluminoxanes are contemplated herein.

In preparing a catalyst composition containing an aluminoxane, the molarratio of the total moles of aluminum in the aluminoxane (oraluminoxanes) to the total moles of metallocene compound(s) in thecomposition is generally between about 1:10 and about 100,000:1. Inanother aspect, the molar ratio is in a range from about 5:1 to about15,000:1. Optionally, aluminoxane can be added to a polymerization zonein ranges from about 0.01 mg/L to about 1000 mg/L, from about 0.1 mg/Lto about 100 mg/L, or from about 1 mg/L to about 50 mg/L.

Organoaluminoxanes can be prepared by various procedures. Examples oforganoaluminoxane preparations are disclosed in U.S. Pat. Nos. 3,242,099and 4,808,561, the disclosures of which are incorporated herein byreference in their entirety. For example, water in an inert organicsolvent can be reacted with an aluminum alkyl compound, such as(R^(C))₃Al, to form the desired organoaluminoxane compound. While notintending to be bound by this statement, it is believed that thissynthetic method can afford a mixture of both linear and cyclic R—Al—Oaluminoxane species, both of which are encompassed by this invention.Alternatively, organoaluminoxanes are prepared by reacting an aluminumalkyl compound, such as (R^(C))₃Al, with a hydrated salt, such ashydrated copper sulfate, in an inert organic solvent.

Organoboron/Organoborate Compounds

According to another aspect of the present invention, the catalystcomposition can comprise an organoboron or organoborate compound. Suchcompounds include neutral boron compounds, borate salts, and the like,or combinations thereof. For example, fluoroorgano boron compounds andfluoroorgano borate compounds are contemplated.

Any fluoroorgano boron or fluoroorgano borate compound can be utilizedwith the present invention. Examples of fluoroorgano borate compoundsthat can be used in the present invention include, but are not limitedto, fluorinated aryl borates such as N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate, triphenylcarbeniumtetrakis(pentafluorophenyl)borate, lithiumtetrakis(pentafluorophenyl)borate, N,N-dimethylaniliniumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, triphenylcarbeniumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, and the like, ormixtures thereof. Examples of fluoroorgano boron compounds that can beused as co-catalysts in the present invention include, but are notlimited to, tris(pentafluorophenyl)boron,tris[3,5-bis(trifluoromethyl)phenyl]boron, and the like, or mixturesthereof. Although not intending to be bound by the following theory,these examples of fluoroorgano borate and fluoroorgano boron compounds,and related compounds, are thought to form “weakly-coordinating” anionswhen combined with organometal or metallocene compounds, as disclosed inU.S. Pat. No. 5,919,983, the disclosure of which is incorporated hereinby reference in its entirety. Applicants also contemplate the use ofdiboron, or bis-boron, compounds or other bifunctional compoundscontaining two or more boron atoms in the chemical structure, such asdisclosed in J. Am. Chem. Soc., 2005, 127, pp. 14756-14768, the contentof which is incorporated herein by reference in its entirety.

Generally, any amount of organoboron compound can be used. According toone aspect of this invention, the molar ratio of the total moles oforganoboron or organoborate compound (or compounds) to the total molesof metallocene compound (or compounds) in the catalyst composition is ina range from about 0.1:1 to about 15:1. Typically, the amount of thefluoroorgano boron or fluoroorgano borate compound used is from about0.5 moles to about 10 moles of boron/borate compound per mole ofmetallocene compound(s). According to another aspect of this invention,the amount of fluoroorgano boron or fluoroorgano borate compound is fromabout 0.8 moles to about 5 moles of boron/borate compound per mole ofmetallocene compound(s).

Ionizing Ionic Compounds

The present invention further provides a catalyst composition which cancomprise an ionizing ionic compound. An ionizing ionic compound is anionic compound that can function as a co-catalyst to enhance theactivity of the catalyst composition. While not intending to be bound bytheory, it is believed that the ionizing ionic compound is capable ofreacting with a metallocene compound and converting the metallocene intoone or more cationic metallocene compounds, or incipient cationicmetallocene compounds. Again, while not intending to be bound by theory,it is believed that the ionizing ionic compound can function as anionizing compound by completely or partially extracting an anionicligand, possibly a non-alkadienyl ligand, from the metallocene. However,the ionizing ionic compound is an activator or co-catalyst regardless ofwhether it is ionizes the metallocene, abstracts a ligand in a fashionas to form an ion pair, weakens the metal-ligand bond in themetallocene, simply coordinates to a ligand, or activates themetallocene by some other mechanism.

Further, it is not necessary that the ionizing ionic compound activatethe metallocene compound(s) only. The activation function of theionizing ionic compound can be evident in the enhanced activity ofcatalyst composition as a whole, as compared to a catalyst compositionthat does not contain an ionizing ionic compound.

Examples of ionizing ionic compounds include, but are not limited to,the following compounds: tri(n-butyl)ammonium tetrakis(p-tolyl)borate,tri(n-butyl) ammonium tetrakis(m-tolyl)borate, tri(n-butyl)ammoniumtetrakis(2,4-dimethylphenyl)borate, tri(n-butyl)ammoniumtetrakis(3,5-dimethylphenyl)borate, tri(n-butyl)ammoniumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, tri(n-butyl)ammoniumtetrakis(pentafluorophenyl)borate, N,N-dimethylaniliniumtetrakis(p-tolyl)borate, N,N-dimethylanilinium tetrakis(m-tolyl)borate,N,N-dimethylanilinium tetrakis(2,4-dimethylphenyl)borate,N,N-dimethylanilinium tetrakis(3,5-dimethyl-phenyl)borate,N,N-dimethylanilinium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate,N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate,triphenylcarbenium tetrakis(p-tolyl)borate, triphenylcarbeniumtetrakis(m-tolyl)borate, triphenylcarbeniumtetrakis(2,4-dimethylphenyl)borate, triphenylcarbeniumtetrakis(3,5-dimethylphenyl)borate, triphenylcarbeniumtetrakis[3,5-bis(trifluoro-methyl)phenyl]borate, triphenylcarbeniumtetrakis(pentafluorophenyl)borate, tropylium tetrakis(p-tolyl)borate,tropylium tetrakis(m-tolyl)borate, tropyliumtetrakis(2,4-dimethylphenyl)borate, tropyliumtetrakis(3,5-dimethylphenyl)borate, tropyliumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, tropyliumtetrakis(pentafluorophenyl)borate, lithiumtetrakis(pentafluorophenyl)borate, lithium tetraphenylborate, lithiumtetrakis(p-tolyl)borate, lithium tetrakis(m-tolyl)borate, lithiumtetrakis(2,4-dimethylphenyl)borate, lithiumtetrakis(3,5-dimethylphenyl)borate, lithium tetrafluoroborate, sodiumtetrakis(pentafluorophenyl)borate, sodium tetraphenylborate, sodiumtetrakis(p-tolyl)borate, sodium tetrakis(m-tolyl)borate, sodiumtetrakis(2,4-dimethylphenyl)borate, sodiumtetrakis(3,5-dimethylphenyl)borate, sodium tetrafluoroborate, potassiumtetrakis(pentafluorophenyl)borate, potassium tetraphenylborate,potassium tetrakis(p-tolyl)borate, potassium tetrakis(m-tolyl)borate,potassium tetrakis(2,4-dimethylphenyl)borate, potassiumtetrakis(3,5-dimethylphenyl)borate, potassium tetrafluoroborate, lithiumtetrakis(pentafluorophenyl)aluminate, lithium tetraphenylaluminate,lithium tetrakis(p-tolyl)aluminate, lithium tetrakis(m-tolyl)aluminate,lithium tetrakis(2,4-dimethylphenyl)aluminate, lithiumtetrakis(3,5-dimethylphenyl)aluminate, lithium tetrafluoroaluminate,sodium tetrakis(pentafluorophenyl)aluminate, sodiumtetraphenylaluminate, sodium tetrakis(p-tolyl)aluminate, sodiumtetrakis(m-tolyl)aluminate, sodiumtetrakis(2,4-dimethylphenyl)aluminate, sodiumtetrakis(3,5-dimethylphenyl)aluminate, sodium tetrafluoroaluminate,potassium tetrakis(pentafluorophenyl)aluminate, potassiumtetraphenylaluminate, potassium tetrakis(p-tolyl)aluminate, potassiumtetrakis(m-tolyl)aluminate, potassiumtetrakis(2,4-dimethylphenyl)aluminate, potassiumtetrakis(3,5-dimethylphenyl)aluminate, potassium tetrafluoroaluminate,and the like, or combinations thereof. Ionizing ionic compounds usefulin this invention are not limited to these; other examples of ionizingionic compounds are disclosed in U.S. Pat. Nos. 5,576,259 and 5,807,938,the disclosures of which are incorporated herein by reference in theirentirety.

Olefin Monomers

Unsaturated reactants that can be employed with catalyst compositionsand polymerization processes of this invention typically include olefincompounds having from 2 to 30 carbon atoms per molecule and having atleast one olefinic double bond. This invention encompasseshomopolymerization processes using a single olefin such as ethylene orpropylene, as well as copolymerization, terpolymerization, etc.,reactions using an olefin monomer with at least one different olefiniccompound. For example, the resultant ethylene copolymers, terpolymers,etc., generally contain a major amount of ethylene (>50 mole percent)and a minor amount of comonomer (<50 mole percent), though this is not arequirement. Comonomers that can be copolymerized with ethylene oftenhave from 3 to 20 carbon atoms in their molecular chain.

Acyclic, cyclic, polycyclic, terminal (a), internal, linear, branched,substituted, unsubstituted, functionalized, and non-functionalizedolefins can be employed in this invention. For example, typicalunsaturated compounds that can be polymerized with the catalystcompositions of this invention include, but are not limited to,ethylene, propylene, 1-butene, 2-butene, 3-methyl-1-butene, isobutylene,1-pentene, 2-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene,2-hexene, 3-hexene, 3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene,the four normal octenes (e.g., 1-octene), the four normal nonenes, thefive normal decenes, and the like, or mixtures of two or more of thesecompounds. Cyclic and bicyclic olefins, including but not limited to,cyclopentene, cyclohexene, norbornylene, norbornadiene, and the like,also can be polymerized as described above. Styrene can also be employedas a monomer in the present invention. In an aspect, the olefin monomeris a C₂-C₁₀ olefin; alternatively, the olefin monomer is ethylene; oralternatively, the olefin monomer is propylene.

When a copolymer (or alternatively, a terpolymer) is desired, the olefinmonomer can comprise, for example, ethylene or propylene, which iscopolymerized with at least one comonomer. According to one aspect ofthis invention, the olefin monomer in the polymerization processcomprises ethylene. In this aspect, examples of suitable olefincomonomers include, but are not limited to, propylene, 1-butene,2-butene, 3-methyl-1-butene, isobutylene, 1-pentene, 2-pentene,3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, 2-hexene,3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene, 1-octene, 1-decene,styrene, and the like, or combinations thereof. According to one aspectof the present invention, the comonomer can comprise 1-butene,1-pentene, 1-hexene, 1-octene, 1-decene, styrene, or any combinationthereof.

Generally, the amount of comonomer introduced into a reactor zone toproduce the copolymer is from about 0.01 to about 50 weight percent ofthe comonomer based on the total weight of the monomer and comonomer.According to another aspect of the present invention, the amount ofcomonomer introduced into a reactor zone is from about 0.01 to about 40weight percent comonomer based on the total weight of the monomer andcomonomer. In still another aspect, the amount of comonomer introducedinto a reactor zone is from about 0.1 to about 35 weight percentcomonomer based on the total weight of the monomer and comonomer. Yet,in another aspect, the amount of comonomer introduced into a reactorzone is from about 0.5 to about 20 weight percent comonomer based on thetotal weight of the monomer and comonomer.

While not intending to be bound by this theory, where branched,substituted, or functionalized olefins are used as reactants, it isbelieved that a steric hindrance can impede and/or slow thepolymerization process. Thus, branched and/or cyclic portion(s) of theolefin removed somewhat from the carbon-carbon double bond would not beexpected to hinder the reaction in the way that the same olefinsubstituents situated more proximate to the carbon-carbon double bondmight. According to one aspect of the present invention, at least onemonomer/reactant is ethylene, so the polymerizations are either ahomopolymerization involving only ethylene, or copolymerizations with adifferent acyclic, cyclic, terminal, internal, linear, branched,substituted, or unsubstituted olefin. In addition, the catalystcompositions of this invention can be used in the polymerization ofdiolefin compounds including, but not limited to, 1,3-butadiene,isoprene, 1,4-pentadiene, and 1,5-hexadiene.

Catalyst Composition

In some aspects, the present invention employs catalyst compositionscontaining an ansa-metallocene compound having formula (I) and anactivator, while in other aspects, the present invention employscatalyst compositions containing an ansa-metallocene compound havingformula (I) and an activator-support. These catalyst compositions can beutilized to produce polyolefins—homopolymers, copolymers, and thelike—for a variety of end-use applications. Metallocene compounds havingformula (I) were discussed above. For instance, in one aspect, theansa-metallocene compound having formula (I) can comprise (or consistessentially of, or consist of) an ansa-metallocene compound havingformula (II), formula (III), formula (IV), formula (V), formula (VI),formula (VII), or combinations thereof. Yet, in another aspect, theansa-metallocene compound having formula (I) can comprise (or consistessentially of, or consist of) an ansa-metallocene compound havingformula (C), formula (D), formula (E), or combinations thereof.

In aspects of the present invention, it is contemplated that thecatalyst composition can contain more than one metallocene compoundhaving formula (I). Further, additional metallocene compounds—other thanthose having formula (I)—can be employed in the catalyst compositionand/or the polymerization process, provided that the additionalmetallocene compound(s) does not detract from the advantages disclosedherein. Additionally, more than one activator and/or more than oneactivator-support also may be utilized.

Generally, catalyst compositions of the present invention comprise anansa-metallocene compound having formula (I) and an activator. Inaspects of the invention, the activator can comprise anactivator-support. Activator-supports useful in the present inventionwere disclosed above. Such catalyst compositions can further compriseone or more than one organoaluminum compound or compounds (suitableorganoaluminum compounds also were discussed above). Thus, a catalystcomposition of this invention can comprise an ansa-metallocene compoundhaving formula (I), an activator-support, and an organoaluminumcompound. For instance, the activator-support can comprise (or consistessentially of, or consist of) fluorided alumina, chlorided alumina,bromided alumina, sulfated alumina, fluorided silica-alumina, chloridedsilica-alumina, bromided silica-alumina, sulfated silica-alumina,fluorided silica-zirconia, chlorided silica-zirconia, bromidedsilica-zirconia, sulfated silica-zirconia, fluorided silica-titania,fluorided silica-coated alumina, sulfated silica-coated alumina,phosphated silica-coated alumina, and the like, or combinations thereof.Additionally, the organoaluminum compound can comprise (or consistessentially of, or consist of) trimethylaluminum, triethylaluminum,tri-n-propylaluminum, tri-n-butylaluminum, triisobutylaluminum,tri-n-hexylaluminum, tri-n-octylaluminum, diisobutylaluminum hydride,diethylaluminum ethoxide, diethylaluminum chloride, and the like, orcombinations thereof.

In another aspect of the present invention, a catalyst composition isprovided which comprises an ansa-metallocene compound having formula(I), an activator-support, and an organoaluminum compound, wherein thiscatalyst composition is substantially free of aluminoxanes, organoboronor organoborate compounds, ionizing ionic compounds, and/or othersimilar materials; alternatively, substantially free of aluminoxanes;alternatively, substantially free or organoboron or organoboratecompounds; or alternatively, substantially free of ionizing ioniccompounds. In these aspects, the catalyst composition has catalystactivity, to be discussed below, in the absence of these additionalmaterials. For example, a catalyst composition of the present inventioncan consist essentially of an ansa-metallocene compound having formula(I), an activator-support, and an organoaluminum compound, wherein noother materials are present in the catalyst composition which wouldincrease/decrease the activity of the catalyst composition by more thanabout 10% from the catalyst activity of the catalyst composition in theabsence of said materials.

However, in other aspects of this invention, theseactivators/co-catalysts can be employed. For example, a catalystcomposition comprising an ansa-metallocene compound having formula (I)and an activator-support can further comprise an optional co-catalyst.Suitable co-catalysts in this aspect include, but are not limited to,aluminoxane compounds, organoboron or organoborate compounds, ionizingionic compounds, and the like, or any combination thereof. More than oneco-catalyst can be present in the catalyst composition.

In a different aspect, a catalyst composition is provided which does notrequire an activator-support. Such a catalyst composition can comprisean ansa-metallocene compound having formula (I) and an activator,wherein the activator comprises an aluminoxane compound, an organoboronor organoborate compound, an ionizing ionic compound, or combinationsthereof.

This invention further encompasses methods of making these catalystcompositions, such as, for example, contacting the respective catalystcomponents in any order or sequence.

The ansa-metallocene compound having formula (I) can be precontactedwith an olefinic monomer if desired, not necessarily the olefin monomerto be polymerized, and an organoaluminum compound for a first period oftime prior to contacting this precontacted mixture with anactivator-support. The first period of time for contact, the precontacttime, between the metallocene compound, the olefinic monomer, and theorganoaluminum compound typically ranges from a time period of about 1minute to about 24 hours, for example, from about 3 minutes to about 1hour. Precontact times from about 10 minutes to about 30 minutes arealso employed. Alternatively, the precontacting process is carried outin multiple steps, rather than a single step, in which multiple mixturesare prepared, each comprising a different set of catalyst components.For example, at least two catalyst components are contacted forming afirst mixture, followed by contacting the first mixture with at leastone other catalyst component forming a second mixture, and so forth.

Multiple precontacting steps can be carried out in a single vessel or inmultiple vessels. Further, multiple precontacting steps can be carriedout in series (sequentially), in parallel, or a combination thereof. Forexample, a first mixture of two catalyst components can be formed in afirst vessel, a second mixture comprising the first mixture plus oneadditional catalyst component can be formed in the first vessel or in asecond vessel, which is typically placed downstream of the first vessel.

In another aspect, one or more of the catalyst components can be splitand used in different precontacting treatments. For example, part of acatalyst component is fed into a first precontacting vessel forprecontacting with at least one other catalyst component, while theremainder of that same catalyst component is fed into a secondprecontacting vessel for precontacting with at least one other catalystcomponent, or is fed directly into the reactor, or a combinationthereof. The precontacting can be carried out in any suitable equipment,such as tanks, stirred mix tanks, various static mixing devices, aflask, a vessel of any type, or combinations of these apparatus.

In another aspect of this invention, the various catalyst components(for example, an ansa-metallocene compound having formula (I),activator-support, organoaluminum co-catalyst, and optionally anunsaturated hydrocarbon) are contacted in the polymerization reactorsimultaneously while the polymerization reaction is proceeding.Alternatively, any two or more of these catalyst components can beprecontacted in a vessel prior to entering the reaction zone. Thisprecontacting step can be continuous, in which the precontacted productis fed continuously to the reactor, or it can be a stepwise or batchwiseprocess in which a batch of precontacted product is added to make acatalyst composition. This precontacting step can be carried out over atime period that can range from a few seconds to as much as severaldays, or longer. In this aspect, the continuous precontacting stepgenerally lasts from about 1 second to about 1 hour. In another aspect,the continuous precontacting step lasts from about 10 seconds to about45 minutes, or from about 1 minute to about 30 minutes.

Once the precontacted mixture of the ansa-metallocene compound havingformula (I), the olefin monomer, and the organoaluminum co-catalyst iscontacted with the activator-support, this composition (with theaddition of the activator-support) is termed the “postcontactedmixture.” The postcontacted mixture optionally remains in contact for asecond period of time, the postcontact time, prior to initiating thepolymerization process. Postcontact times between the precontactedmixture and the activator-support generally range from about 1 minute toabout 24 hours. In a further aspect, the postcontact time is in a rangefrom about 3 minutes to about 1 hour. The precontacting step, thepostcontacting step, or both, can increase the productivity of thepolymer as compared to the same catalyst composition that is preparedwithout precontacting or postcontacting. However, neither aprecontacting step nor a postcontacting step is required.

The postcontacted mixture can be heated at a temperature and for a timeperiod sufficient to allow adsorption, impregnation, or interaction ofprecontacted mixture and the activator-support, such that a portion ofthe components of the precontacted mixture is immobilized, adsorbed, ordeposited thereon. Where heating is employed, the postcontacted mixturegenerally is heated to a temperature of from between about 0° F. toabout 150° F., or from about 40° F. to about 95° F.

When a precontacting step is used, the molar ratio of the total moles ofolefin monomer to total moles of metallocene(s) in the precontactedmixture is typically in a range from about 1:10 to about 100,000:1.Total moles of each component are used in this ratio to account foraspects of this invention where more than one olefin monomer and/or morethan one metallocene compound is employed in a precontacting step.Further, this molar ratio can be in a range from about 10:1 to about1,000:1 in another aspect of the invention.

Generally, the weight ratio of organoaluminum compound toactivator-support is in a range from about 10:1 to about 1:1000. If morethan one organoaluminum compound and/or more than one activator-supportis employed, this ratio is based on the total weight of each respectivecomponent. In another aspect, the weight ratio of the organoaluminumcompound to the activator-support is in a range from about 3:1 to about1:100, or from about 1:1 to about 1:50.

In some aspects of this invention, the weight ratio of metallocenecompound(s) to activator-support is in a range from about 1:1 to about1:1,000,000. If more than one activator-support is employed, this ratiois based on the total weight of the activator-support. In anotheraspect, this weight ratio is in a range from about 1:5 to about1:100,000, or from about 1:10 to about 1:10,000. Yet, in another aspect,the weight ratio of the metallocene compound(s) to the activator-supportis in a range from about 1:20 to about 1:1000.

Catalyst compositions of the present invention generally have a catalystactivity greater than about 100 grams of polyethylene (homopolymer,copolymer, etc., as the context requires) per gram of activator-supportper hour (abbreviated g/g/hr). In another aspect, the catalyst activityis greater than about 150, greater than about 250, or greater than about500 g/g/hr. In still another aspect, catalyst compositions of thisinvention can be characterized by having a catalyst activity greaterthan about 550, greater than about 650, or greater than about 750g/g/hr. Yet, in another aspect, the catalyst activity can be greaterthan about 1000 g/g/hr. This activity is measured under slurrypolymerization conditions using isobutane as the diluent, at apolymerization temperature of about 90° C. and a reactor pressure ofabout 390 psig.

In accordance with another aspect of the present invention, catalystcompositions disclosed herein can have a catalyst activity greater thanabout 10 grams of polyethylene (homopolymer, copolymer, etc., as thecontext requires) per μmol of metallocene per hour (abbreviatedg/μmol/hr). An activity of 10 g/μmol/hr equates to an activity of 10,000kg/mol/hr. In another aspect, the catalyst activity of the catalystcomposition can be greater than about 15, greater than about 20, orgreater than about 25 g/μmol/hr. In still another aspect, catalystcompositions of this invention can be characterized by having a catalystactivity greater than about 30, greater than about 40, or greater thanabout 50 g/μmol/hr. Yet, in another aspect, the catalyst activity can begreater than about 100 g/μmol/hr. This activity is measured under slurrypolymerization conditions using isobutane as the diluent, at apolymerization temperature of about 90° C. and a reactor pressure ofabout 390 psig.

As discussed above, any combination of the ansa-metallocene compoundhaving formula (I), the activator-support, the organoaluminum compound,and the olefin monomer, can be precontacted in some aspects of thisinvention. When any precontacting occurs with an olefinic monomer, it isnot necessary that the olefin monomer used in the precontacting step bethe same as the olefin to be polymerized. Further, when a precontactingstep among any combination of the catalyst components is employed for afirst period of time, this precontacted mixture can be used in asubsequent postcontacting step between any other combination of catalystcomponents for a second period of time. For example, the metallocenecompound, the organoaluminum compound, and 1-hexene can be used in aprecontacting step for a first period of time, and this precontactedmixture then can be contacted with the activator-support to form apostcontacted mixture that is contacted for a second period of timeprior to initiating the polymerization reaction. For example, the firstperiod of time for contact, the precontact time, between any combinationof the metallocene compound, the olefinic monomer, theactivator-support, and the organoaluminum compound can be from about 1minute to about 24 hours, from about 3 minutes to about 1 hour, or fromabout 10 minutes to about 30 minutes. The postcontacted mixtureoptionally is allowed to remain in contact for a second period of time,the postcontact time, prior to initiating the polymerization process.According to one aspect of this invention, postcontact times between theprecontacted mixture and any remaining catalyst components is from about1 minute to about 24 hours, or from about 5 minutes to about 1 hour.

Polymerization Process

Catalyst compositions of the present invention can be used to polymerizeolefins to form homopolymers, copolymers, terpolymers, and the like. Onesuch process for polymerizing olefins in the presence of a catalystcomposition of the present invention comprises contacting the catalystcomposition with an olefin monomer and optionally an olefin comonomer(one or more) under polymerization conditions to produce an olefinpolymer, wherein the catalyst composition comprises an ansa-metallocenecompound having formula (I) and an activator. Metallocene compoundshaving formula (I):E(Cp^(A)R^(A) _(m))(Cp^(B)R^(B) _(n))MX_(q)  (I),were discussed above. For instance, in one aspect, the ansa-metallocenecompound having formula (I) can comprise (or consist essentially of, orconsist of) an ansa-metallocene compound having formula (II), formula(III), formula (IV), formula (V), formula (VI), formula (VII), orcombinations thereof. Yet, in another aspect, the ansa-metallocenecompound having formula (I) can comprise (or consist essentially of, orconsist of) an ansa-metallocene compound having formula (C), formula(D), formula (E), or combinations thereof.

In accordance with one aspect of the invention, the polymerizationprocess employs a catalyst composition comprising an ansa-metallocenecompound having formula (I) and an activator, wherein the activatorcomprises an activator-support. Activator-supports useful in thepolymerization processes of the present invention were disclosed above.The catalyst composition can further comprise one or more than oneorganoaluminum compound or compounds (suitable organoaluminum compoundsalso were discussed above). Thus, a process for polymerizing olefins inthe presence of a catalyst composition can employ a catalyst compositioncomprising an ansa-metallocene compound having formula (I), anactivator-support, and an organoaluminum compound. In some aspects, theactivator-support can comprise (or consist essentially of, or consistof) fluorided alumina, chlorided alumina, bromided alumina, sulfatedalumina, fluorided silica-alumina, chlorided silica-alumina, bromidedsilica-alumina, sulfated silica-alumina, fluorided silica-zirconia,chlorided silica-zirconia, bromided silica-zirconia, sulfatedsilica-zirconia, fluorided silica-titania, fluorided silica-coatedalumina, sulfated silica-coated alumina, phosphated silica-coatedalumina, and the like, or combinations thereof. In some aspects, theorganoaluminum compound can comprise (or consist essentially of, orconsist of) trimethylaluminum, triethylaluminum, tri-n-propylaluminum,tri-n-butylaluminum, triisobutylaluminum, tri-n-hexylaluminum,tri-n-octylaluminum, diisobutylaluminum hydride, diethylaluminumethoxide, diethylaluminum chloride, and the like, or combinationsthereof.

In accordance with another aspect of the invention, the polymerizationprocess can employ a catalyst composition comprising an ansa-metallocenecompound having formula (I) and an activator, wherein the activatorcomprises an aluminoxane compound, an organoboron or organoboratecompound, an ionizing ionic compound, or combinations thereof.

The catalyst compositions of the present invention are intended for anyolefin polymerization method using various types of polymerizationreactors. As used herein, “polymerization reactor” includes anypolymerization reactor capable of polymerizing olefin monomers andcomonomers (one or more than one comonomer) to produce homopolymers,copolymers, terpolymers, and the like. The various types of reactorsinclude those that may be referred to as a batch reactor, slurryreactor, gas-phase reactor, solution reactor, high pressure reactor,tubular reactor, autoclave reactor, and the like, or combinationsthereof. The polymerization conditions for the various reactor types arewell known to those of skill in the art. Gas phase reactors may comprisefluidized bed reactors or staged horizontal reactors. Slurry reactorsmay comprise vertical or horizontal loops. High pressure reactors maycomprise autoclave or tubular reactors. Reactor types can include batchor continuous processes. Continuous processes could use intermittent orcontinuous product discharge. Processes may also include partial or fulldirect recycle of unreacted monomer, unreacted comonomer, and/ordiluent.

Polymerization reactor systems of the present invention may comprise onetype of reactor in a system or multiple reactors of the same ordifferent type. Production of polymers in multiple reactors may includeseveral stages in at least two separate polymerization reactorsinterconnected by a transfer device making it possible to transfer thepolymers resulting from the first polymerization reactor into the secondreactor. The desired polymerization conditions in one of the reactorsmay be different from the operating conditions of the other reactors.Alternatively, polymerization in multiple reactors may include themanual transfer of polymer from one reactor to subsequent reactors forcontinued polymerization. Multiple reactor systems may include anycombination including, but not limited to, multiple loop reactors,multiple gas phase reactors, a combination of loop and gas phasereactors, multiple high pressure reactors, or a combination of highpressure with loop and/or gas phase reactors. The multiple reactors maybe operated in series, in parallel, or both.

According to one aspect of the invention, the polymerization reactorsystem may comprise at least one loop slurry reactor comprising verticalor horizontal loops. Monomer, diluent, catalyst, and comonomer may becontinuously fed to a loop reactor where polymerization occurs.Generally, continuous processes may comprise the continuous introductionof monomer/comonomer, a catalyst, and a diluent into a polymerizationreactor and the continuous removal from this reactor of a suspensioncomprising polymer particles and the diluent. Reactor effluent may beflashed to remove the solid polymer from the liquids that comprise thediluent, monomer and/or comonomer. Various technologies may be used forthis separation step including but not limited to, flashing that mayinclude any combination of heat addition and pressure reduction;separation by cyclonic action in either a cyclone or hydrocyclone; orseparation by centrifugation.

A typical slurry polymerization process (also known as the particle formprocess) is disclosed, for example, in U.S. Pat. Nos. 3,248,179,4,501,885, 5,565,175, 5,575,979, 6,239,235, 6,262,191, and 6,833,415,each of which is incorporated herein by reference in its entirety.

Suitable diluents used in slurry polymerization include, but are notlimited to, the monomer being polymerized and hydrocarbons that areliquids under reaction conditions. Examples of suitable diluentsinclude, but are not limited to, hydrocarbons such as propane,cyclohexane, isobutane, n-butane, n-pentane, isopentane, neopentane, andn-hexane. Some loop polymerization reactions can occur under bulkconditions where no diluent is used. An example is polymerization ofpropylene monomer as disclosed in U.S. Pat. No. 5,455,314, which isincorporated by reference herein in its entirety.

According to yet another aspect of this invention, the polymerizationreactor may comprise at least one gas phase reactor. Such systems mayemploy a continuous recycle stream containing one or more monomerscontinuously cycled through a fluidized bed in the presence of thecatalyst under polymerization conditions. A recycle stream may bewithdrawn from the fluidized bed and recycled back into the reactor.Simultaneously, polymer product may be withdrawn from the reactor andnew or fresh monomer may be added to replace the polymerized monomer.Such gas phase reactors may comprise a process for multi-step gas-phasepolymerization of olefins, in which olefins are polymerized in thegaseous phase in at least two independent gas-phase polymerization zoneswhile feeding a catalyst-containing polymer formed in a firstpolymerization zone to a second polymerization zone. One type of gasphase reactor is disclosed in U.S. Pat. Nos. 5,352,749, 4,588,790, and5,436,304, each of which is incorporated by reference in its entiretyherein.

According to still another aspect of the invention, a high pressurepolymerization reactor may comprise a tubular reactor or an autoclavereactor. Tubular reactors may have several zones where fresh monomer,initiators, or catalysts are added. Monomer may be entrained in an inertgaseous stream and introduced at one zone of the reactor. Initiators,catalysts, and/or catalyst components may be entrained in a gaseousstream and introduced at another zone of the reactor. The gas streamsmay be intermixed for polymerization. Heat and pressure may be employedappropriately to obtain optimal polymerization reaction conditions.

According to yet another aspect of the invention, the polymerizationreactor may comprise a solution polymerization reactor wherein themonomer/comonomer are contacted with the catalyst composition bysuitable stirring or other means. A carrier comprising an inert organicdiluent or excess monomer may be employed. If desired, themonomer/comonomer may be brought in the vapor phase into contact withthe catalytic reaction product, in the presence or absence of liquidmaterial. The polymerization zone is maintained at temperatures andpressures that will result in the formation of a solution of the polymerin a reaction medium. Agitation may be employed to obtain bettertemperature control and to maintain uniform polymerization mixturesthroughout the polymerization zone. Adequate means are utilized fordissipating the exothermic heat of polymerization.

Polymerization reactors suitable for the present invention may furthercomprise any combination of at least one raw material feed system, atleast one feed system for catalyst or catalyst components, and/or atleast one polymer recovery system. Suitable reactor systems for thepresent invention may further comprise systems for feedstockpurification, catalyst storage and preparation, extrusion, reactorcooling, polymer recovery, fractionation, recycle, storage, loadout,laboratory analysis, and process control.

Polymerization conditions that are controlled for efficiency and toprovide desired polymer properties can include temperature, pressure,and the concentrations of various reactants. Polymerization temperaturecan affect catalyst productivity, polymer molecular weight, andmolecular weight distribution. A suitable polymerization temperature maybe any temperature below the de-polymerization temperature according tothe Gibbs Free energy equation. Typically, this includes from about 60°C. to about 280° C., for example, or from about 60° C. to about 110° C.,depending upon the type of polymerization reactor. In some reactorsystems, the polymerization temperature generally is within a range fromabout 70° C. to about 90° C., or from about 75° C. to about 85° C.

Suitable pressures will also vary according to the reactor andpolymerization type. The pressure for liquid phase polymerizations in aloop reactor is typically less than 1000 psig. Pressure for gas phasepolymerization is usually at about 200 to 500 psig. High pressurepolymerization in tubular or autoclave reactors is generally run atabout 20,000 to 75,000 psig. Polymerization reactors can also beoperated in a supercritical region occurring at generally highertemperatures and pressures. Operation above the critical point of apressure/temperature diagram (supercritical phase) may offer advantages.

Aspects of this invention are directed to olefin polymerizationprocesses comprising contacting a catalyst composition with an olefinmonomer and optionally an olefin comonomer under polymerizationconditions to produce an olefin polymer. The olefin polymer produced bythe process can have a density greater than about 0.92 g/cm³, forinstance, in a range from about 0.935 to about 0.97 g/cm³. In addition,or alternatively, the olefin polymer can have an average of less thanabout 5 short chain branches (SCB's) per 1000 total carbon atoms, forinstance, from 0 to about 4 SCB's per 1000 total carbon atoms. Inaddition, or alternatively, the olefin polymer can have less than about0.005 long chain branches (LCB's) per 1000 total carbon atoms, forinstance, less than about 0.002, or less than about 0.001, LCB's per1000 total carbon atoms.

Aspects of this invention also are directed to olefin polymerizationprocesses conducted in the absence of added hydrogen. In thisdisclosure, “added hydrogen” will be denoted as the feed ratio ofhydrogen to olefin monomer entering the reactor (in units of ppm). Anolefin polymerization process of this invention can comprise contactinga catalyst composition with an olefin monomer and optionally an olefincomonomer under polymerization conditions to produce an olefin polymer,wherein the catalyst composition comprises an ansa-metallocene compoundhaving formula (I) and an activator, wherein the polymerization processis conducted in the absence of added hydrogen. As disclosed above, theansa-metallocene compound having formula (I) can comprise anansa-metallocene compound having formula (II), formula (III), formula(IV), formula (V), formula (VI), formula (VII), formula (C), formula(D), formula (E), or combinations thereof. As one of ordinary skill inthe art would recognize, hydrogen can be generated in-situ bymetallocene catalyst compositions in various olefin polymerizationprocesses, and the amount generated may vary depending upon the specificcatalyst composition and metallocene compound(s) employed, the type ofpolymerization process used, the polymerization reaction conditionsutilized, and so forth.

In one aspect, the polymerization process is conducted in the absence ofadded hydrogen, and the Mw/Mn ratio of the olefin polymer produced bythe process can increase as the molar ratio of olefin comonomer toolefin monomer increases from about 0.001:1 to about 0.06:1. Forinstance, the Mw/Mn of the polymer produced by the process at acomonomer:monomer molar ratio of 0.06:1 can be greater than the Mw/Mn ofthe polymer produced by the process at a comonomer:monomer molar ratioof 0.005:1, when produced under the same polymerization conditions.Additionally, the Mw/Mn of the polymer produced by the process at acomonomer:monomer molar ratio of 0.05:1 can be greater than the Mw/Mn ofthe polymer produced by the process at a comonomer:monomer molar ratioof 0.01:1, when produced under the same polymerization conditions.Applicants also contemplate a method of increasing a Mw/Mn ratio of anolefin polymer, and this method comprises contacting a catalystcomposition with an olefin monomer and an olefin comonomer underpolymerization conditions to produce the olefin polymer; contacting thecatalyst composition with the olefin monomer and the olefin comonomer inthe absence of added hydrogen; and increasing the molar ratio of olefincomonomer to olefin monomer within the range of from about 0.001:1 toabout 0.2:1, wherein the catalyst composition comprises anansa-metallocene compound having formula (I) and an activator (e.g., anactivator-support). For instance, the molar ratio can be increased froma lower ratio (e.g., 0.001:1, 0.005:1, etc.) to a higher ratio (e.g.,0.01:1, 0.05:1).

In other aspects, it may be desirable to conduct the polymerizationprocess in the presence of a certain amount of added hydrogen.Accordingly, an olefin polymerization process of this invention cancomprise contacting a catalyst composition with an olefin monomer andoptionally an olefin comonomer under polymerization conditions toproduce an olefin polymer, wherein the catalyst composition comprises anansa-metallocene compound having formula (I) and an activator, whereinthe polymerization process is conducted in the presence of addedhydrogen. For example, the ratio of hydrogen to the olefin monomer inthe polymerization process can be controlled, often by the feed ratio ofhydrogen to the olefin monomer entering the reactor. The added hydrogento olefin monomer ratio in the process can be controlled at a weightratio which falls within a range from about 25 ppm to about 1500 ppm,from about 50 to about 1000 ppm, or from about 100 ppm to about 750 ppm.

In another aspect, the polymerization process is conducted in thepresence of added hydrogen and the olefin comonomer, and the Mw of theolefin polymer is substantially constant over a range of from about 50ppm to about 1000 ppm added hydrogen; alternatively, from about 75 ppmto about 750 ppm added hydrogen; alternatively, from about 75 ppm toabout 500 ppm added hydrogen; or alternatively, from about 100 ppm toabout 500 ppm added hydrogen. As it pertains to the Mw of the olefinpolymer, substantially constant means +/−25%. In some aspects, however,the Mw can be within a +/−15% range. Applicants also contemplate amethod of producing an olefin polymer having a Mw that is substantiallyindependent of hydrogen content, and this method comprises contacting acatalyst composition with an olefin monomer and an olefin comonomerunder polymerization conditions to produce the olefin polymer; andcontacting the catalyst composition with the olefin monomer and theolefin comonomer in the presence of added hydrogen in the range of fromabout 50 ppm to about 1000 ppm (alternatively, from about 75 ppm toabout 750 ppm; alternatively, from about 75 ppm to about 500 ppm; oralternatively, from about 100 ppm to about 500 ppm), wherein thecatalyst composition comprises an ansa-metallocene compound havingformula (I) and an activator (e.g., an activator-support). Similar toabove, the olefin polymer having a Mw that is substantially independentof hydrogen content means that the Mw stays within a +/−25% range in thetargeted range of ppm added hydrogen (e.g., from 100 to 500 ppm). Often,the Mw will fall within a +/−15% range over certain hydrogen contentranges.

In another aspect, an olefin polymerization process can comprisecontacting a catalyst composition with an olefin monomer and optionallyan olefin comonomer under polymerization conditions to produce an olefinpolymer, wherein the catalyst composition comprises an ansa-metallocenecompound having formula (I) and an activator, wherein the polymerizationprocess is conducted in the presence of hydrogen added in a range offrom about 50 ppm to about 1000 ppm hydrogen, or from about 75 ppm toabout 750 ppm, or from about 75 ppm to about 500 ppm, or from about 100ppm to about 500 ppm. In the presence of these ppm hydrogen contents, aMw of an olefin polymer produced by the process in the presence of anolefin comonomer can be at least 25% greater than a Mw of an olefinpolymer produced by the process under the same polymerization conditionswithout the olefin comonomer (e.g., from 25% to 200% greater, from 30%to 100% greater, etc.). For instance, the Mw of the olefin polymerproduced by the process in the presence of the olefin comonomer can beat least 30% greater, 40% greater, 50% greater, or 60% greater, than aMw of an olefin polymer produced by the process under the samepolymerization conditions without the olefin comonomer. Similarly, inthe presence of these ppm added hydrogen contents, a Mw/Mn ratio of anolefin polymer produced by the process in the presence of an olefincomonomer can be at least 15% greater than a Mw/Mn ratio of an olefinpolymer produced by the process under the same polymerization conditionswithout the olefin comonomer (e.g., from 15% to 200% greater, from 15%to 100% greater, etc.). As further examples, the Mw/Mn ratio of theolefin polymer produced by the process in the presence of the olefincomonomer can be at least 20% greater, 25% greater, 30% greater, 40%greater, or 50% greater, than a Mw/Mn of an olefin polymer produced bythe process under the same polymerization conditions without the olefincomonomer. Applicants also contemplate a method of increasing the Mw (orMw/Mn ratio) of an olefin polymer, and this method comprises introducingan olefin comonomer to a contact product of a catalyst composition anolefin monomer under polymerization conditions to produce the olefinpolymer; and introducing the olefin comonomer to the contact product ofthe catalyst composition and the olefin monomer in the presence of addedhydrogen in the range of from about 50 ppm to about 1000 ppm(alternatively, from about 75 ppm to about 750 ppm; alternatively, fromabout 75 ppm to about 500 ppm; or alternatively, from about 100 ppm toabout 500 ppm), wherein the catalyst composition comprises anansa-metallocene compound having formula (I) and an activator (e.g., anactivator-support). The Mw (or Mw/Mn ratio) may be increased by theintroduction of the olefin comonomer by at least 15%, at least 20%, atleast 25%, at least 30%, at least 35%, at least 40%, at least 45%, or atleast 50%, as compared to the Mw (or Mw/Mn ratio) of the olefin polymerproduced in the absence of the olefin comonomer (e.g., from 15% to 200%greater, from 20% to 150% greater, etc.). Typically, the amount ofcomonomer introduced is in a molar ratio of olefin comonomer to olefinmonomer range of from about 0.001:1 to about 0.2:1, or from about0.005:1 to about 0.1:1, or from about 0.01:1 to about 0.05:1.

In another aspect, the catalyst activity of the catalyst composition mayvary with comonomer content and/or may be substantially constant withadded hydrogen content. For example, an olefin polymerization process ofthis invention can comprise contacting a catalyst composition with anolefin monomer and optionally an olefin comonomer under polymerizationconditions to produce an olefin polymer, wherein the activity of thecatalyst composition can decrease as the molar ratio of olefin comonomerto olefin monomer increases from about 0.001:1 to about 0.06:1.Accordingly, the activity of the catalyst composition at acomonomer:monomer molar ratio of 0.06:1 can be less than the activity ofthe catalyst composition at a comonomer:monomer molar ratio of 0.005:1,when determined under the same polymerization conditions. Additionally,the activity of the catalyst composition at a comonomer:monomer molarratio of 0.05:1 can be less than the activity of the catalystcomposition at a comonomer:monomer molar ratio of 0.01:1, whendetermined under the same polymerization conditions. Applicants alsocontemplate a method of increasing the activity of a catalystcomposition, and this method comprises contacting the catalystcomposition with an olefin monomer and an olefin comonomer underpolymerization conditions to produce the olefin polymer; and decreasingthe molar ratio of olefin comonomer to olefin monomer within the rangeof from about 0.2:1 to about 0.001:1, wherein the catalyst compositioncomprises an ansa-metallocene compound having formula (I) and anactivator (e.g., an activator-support). For instance, the molar ratiocan be decreased from a higher ratio (e.g., 0.01:1, 0.05:1) to a lowerratio (e.g., 0.001:1, 0.005:1, etc.).

In another aspect, an olefin polymerization process of this inventioncan comprise contacting a catalyst composition with an olefin monomerand an olefin comonomer under polymerization conditions to produce anolefin polymer, wherein the catalyst composition comprises anansa-metallocene compound having formula (I) and an activator, whereinthe polymerization process is conducted in the presence of addedhydrogen, and wherein the activity of the catalyst composition issubstantially constant over a range of from about 50 ppm to about 1000ppm added hydrogen; alternatively, from about 75 ppm to about 750 ppmadded hydrogen; alternatively, from about 75 ppm to about 500 ppm addedhydrogen; or alternatively, from about 100 ppm to about 500 ppm addedhydrogen. As it pertains to the activity of the catalyst composition,substantially constant means +/−25%. In some aspects, however, theactivity of the catalyst composition can be within a +/−15% range. Thiscatalyst activity can be substantially constant at a given comonomerconcentration. Applicants also contemplate a method of producing anolefin polymer at a catalyst activity that is substantially independentof hydrogen content, and this method comprises contacting a catalystcomposition with an olefin monomer and an olefin comonomer underpolymerization conditions to produce the olefin polymer; and contactingthe catalyst composition with the olefin monomer and the olefincomonomer in the presence of added hydrogen in the range of from about50 ppm to about 1000 ppm (alternatively, from about 75 ppm to about 750ppm; alternatively, from about 75 ppm to about 500 ppm; oralternatively, from about 100 ppm to about 500 ppm), wherein thecatalyst composition comprises an ansa-metallocene compound havingformula (I) and an activator (e.g., an activator-support). Similar toabove, the catalyst composition having an activity that is substantiallyindependent of hydrogen content means that the catalyst activity stayswithin a +/−25% range in the targeted range of ppm added hydrogen (e.g.,from 100 to 500 ppm). Often, the catalyst activity will fall within a+/−15% range over certain hydrogen content ranges.

In some aspects of this invention, the feed or reactant ratio ofhydrogen to olefin monomer can be maintained substantially constantduring the polymerization run for a particular polymer grade. That is,the hydrogen:olefin monomer ratio can be selected at a particular ratiowithin a range from about 5 ppm up to about 1000 ppm or so, andmaintained at the ratio to within about +/−25% during the polymerizationrun. For instance, if the target ratio is 100 ppm, then maintaining thehydrogen:olefin monomer ratio substantially constant would entailmaintaining the feed ratio between about 75 ppm and about 125 ppm.Further, the addition of comonomer (or comonomers) can be, and generallyis, substantially constant throughout the polymerization run for aparticular polymer grade.

However, in other aspects, it is contemplated that monomer, comonomer(or comonomers), and/or hydrogen can be periodically pulsed to thereactor, for instance, in a manner similar to that employed in U.S. Pat.No. 5,739,220 and U.S. Patent Publication No. 2004/0059070, thedisclosures of which are incorporated herein by reference in theirentirety.

The concentration of the reactants entering the polymerization reactorcan be controlled to produce resins with certain physical and mechanicalproperties. The proposed end-use product that will be formed by thepolymer resin and the method of forming that product ultimately candetermine the desired polymer properties and attributes. Mechanicalproperties include tensile, flexural, impact, creep, stress relaxation,and hardness tests. Physical properties include density, molecularweight, molecular weight distribution, melting temperature, glasstransition temperature, temperature melt of crystallization, density,stereoregularity, crack growth, long chain branching, and rheologicalmeasurements.

This invention is also directed to, and encompasses, the polymersproduced by any of the polymerization processes disclosed herein.Articles of manufacture can be formed from, and/or can comprise, thepolymers produced in accordance with this invention.

Polymers and Articles

If the resultant polymer produced in accordance with the presentinvention is, for example, a polymer or copolymer of ethylene, itsproperties can be characterized by various analytical techniques knownand used in the polyolefin industry. Articles of manufacture can beformed from, and/or can comprise, the ethylene polymers of thisinvention, whose typical properties are provided below.

Polymers of ethylene (copolymers, terpolymers, etc.) produced inaccordance with this invention generally have a melt index from 0 toabout 100 g/10 min. Melt indices in the range from 0 to about 75 g/10min, from 0 to about 50 g/10 min, or from 0 to about 30 g/10 min, arecontemplated in some aspects of this invention. For example, a polymerof the present invention can have a melt index (MI) in a range from 0 toabout 25, or from 0 to about 10 g/10 min.

Ethylene polymers produced in accordance with this invention can have aratio of HLMI/MI of greater than about 5, such as, for example, greaterthan about 10, greater than about 15, or greater than about 20.Contemplated ranges for HLMI/MI include, but are not limited to, fromabout 5 to about 150, from about 10 to about 125, from about 10 to about100, from about 15 to about 90, from about 15 to about 80, from about 15to about 70, or from about 15 to about 65.

In some aspects of this invention, the catalyst systems disclosed hereinmay be referred to as comonomer rejecters, i.e., comonomer is not asreadily incorporated into an olefin polymer when compared to otherbridged metallocene catalyst systems. Accordingly, the densities ofethylene-based polymers produced using the catalyst systems andprocesses disclosed herein often are greater than about 0.92 g/cm³. Inone aspect of this invention, the density of an ethylene polymer can begreater than about 0.925, greater than about 0.93, or greater than about0.935 g/cm³. Yet, in another aspect, the density can be in a range fromabout 0.92 to about 0.97 g/cm³, such as, for example, from about 0.925to about 0.97 g/cm³, from about 0.93 to about 0.965 g/cm³, or from about0.935 to about 0.965 g/cm³.

Ethylene polymers of this invention generally can have an average offrom 0 to about 5 short chain branches (SCB's) per 1000 total carbonatoms. For example, average SCB contents in a range from 0 to about 4.5,from 0 to about 4, from 0 to about 3.5, or from 0 to about 3, SCB's per1000 total carbon atoms are contemplated herein.

Ethylene polymers, such as copolymers and terpolymers, within the scopeof the present invention generally have a polydispersity index—a ratioof the weight-average molecular weight (Mw) to the number-averagemolecular weight (Mn)—in a range from 2 to about 10. In some aspectsdisclosed herein, the ratio of Mw/Mn is in a range from about 2.1 toabout 9, from about 2.1 to about 8, or from about 2.2 to about 7. Theratio of Mz/Mw for the polymers of this invention often is in a rangefrom about 1.6 to about 12. Mz is the z-average molecular weight. Inaccordance with one aspect, the Mz/Mw of the ethylene polymers of thisinvention can be in a range from about 1.6 to about 10, from about 1.7to about 6, from about 1.7 to about 4, or from about 1.7 to about 3.5.

Generally, olefin polymers of the present invention have low levels oflong chain branching, with typically less than 0.05 long chain branches(LCB's) per 1000 total carbon atoms. In some aspects, the number ofLCB's per 1000 total carbon atoms is less than about 0.02, less thanabout 0.01, or less than about 0.008. Furthermore, olefin polymers ofthe present invention (e.g., ethylene polymers) can have less than about0.005, less than about 0.004, less than about 0.003, less than about0.002, or less than about 0.001 LCB's per 1000 total carbon atoms, inother aspects of this invention.

Polymers of ethylene, whether homopolymers, copolymers, terpolymers, andso forth, can be formed into various articles of manufacture. Articleswhich can comprise polymers of this invention include, but are notlimited to, an agricultural film, an automobile part, a bottle, a drum,a fiber or fabric, a food packaging film or container, a food servicearticle, a fuel tank, a geomembrane, a household container, a liner, amolded product, a medical device or material, a pipe, a sheet or tape, atoy, and the like. Various processes can be employed to form thesearticles. Non-limiting examples of these processes include injectionmolding, blow molding, rotational molding, film extrusion, sheetextrusion, profile extrusion, thermoforming, and the like. Additionally,additives and modifiers are often added to these polymers in order toprovide beneficial polymer processing or end-use product attributes.

EXAMPLES

The invention is further illustrated by the following examples, whichare not to be construed in any way as imposing limitations to the scopeof this invention. Various other aspects, embodiments, modifications,and equivalents thereof which, after reading the description herein, maysuggest themselves to one of ordinary skill in the art without departingfrom the spirit of the present invention or the scope of the appendedclaims.

Melt index (MI, g/10 min) was determined in accordance with ASTM D1238at 190° C. with a 2,160 gram weight.

High load melt index (HLMI, g/10 min) was determined in accordance withASTM D1238 at 190° C. with a 21,600 gram weight.

Polymer density was determined in grams per cubic centimeter (g/cm³) ona compression molded sample, cooled at about 15° C. per hour, andconditioned for about 40 hours at room temperature in accordance withASTM D1505 and ASTM D1928, procedure C.

Molecular weights and molecular weight distributions were obtained usinga PL 220 SEC high temperature chromatography unit (Polymer Laboratories)with trichlorobenzene (TCB) as the solvent, with a flow rate of 1mL/minute at a temperature of 145° C. BHT(2,6-di-tert-butyl-4-methylphenol) at a concentration of 0.5 g/L wasused as a stabilizer in the TCB. An injection volume of 200 μL was usedwith a nominal polymer concentration of 1.5 mg/mL. Dissolution of thesample in stabilized TCB was carried out by heating at 150° C. for 5hours with occasional, gentle agitation. The columns used were threePLgel Mixed A LS columns (7.8×300 mm) and were calibrated with a broadlinear polyethylene standard (Phillips Marlex® BHB 5003) for which themolecular weight had been determined.

SEC-MALS combines the methods of size exclusion chromatography (SEC)with multi-angle light scattering (MALS) detection. A DAWN EOS 18-anglelight scattering photometer (Wyatt Technology, Santa Barbara, Calif.)was attached to a PL-210 SEC system (Polymer Labs, UK) or a Waters 150CV Plus system (Milford, Mass.) through a hot transfer line, thermallycontrolled at the same temperature as the SEC columns and itsdifferential refractive index (DRI) detector (145° C.). At a flow ratesetting of 0.7 mL/min, the mobile phase, 1,2,4-trichlorobenzene (TCB),was eluted through three, 7.5 mm×300 mm, 20 μm Mixed A-LS columns(Polymer Labs). Polyethylene (PE) solutions with concentrations of −1.2mg/mL, depending on samples, were prepared at 150° C. for 4 h beforebeing transferred to the SEC injection vials sitting in a carouselheated at 145° C. For polymers of higher molecular weight, longerheating times were necessary in order to obtain true homogeneoussolutions. In addition to acquiring a concentration chromatogram,seventeen light-scattering chromatograms at different angles were alsoacquired for each injection using Wyatt's Astra® software. At eachchromatographic slice, both the absolute molecular weight (M) and rootmean square (RMS) radius, also known as radius of gyration (Rg) wereobtained from a Debye plot's intercept and slope, respectively. Methodsfor this process are detailed in Wyatt, P. J., Anal. Chim. Acta, 272, 1(1993), which is incorporated herein by reference in its entirety.

The Zimm-Stockmayer approach was used to determine the amount of LCB.Since SEC-MALS measures M and Rg at each slice of a chromatogramsimultaneously, the branching indices, g_(M), as a function of M couldbe determined at each slice directly by determining the ratio of themean square Rg of branched molecules to that of linear ones, at the sameM, as shown in following equation (subscripts br and lin representbranched and linear polymers, respectively).

$g_{M} = {\frac{\left\langle R_{g} \right\rangle_{br}^{2}}{\left\langle R_{g} \right\rangle_{lin}^{2}}.}$

At a given g_(M), the weight-averaged number of LCB per molecule(B_(3w)) was computed using Zimm-Stockmayer's equation, shown in theequation below, where the branches were assumed to be trifunctional, orY-shaped.

$g_{M} = {\frac{6}{B_{3w}}{\left\{ {{\frac{1}{2}\left( \frac{2 + B_{3w}}{B_{3w}} \right)^{1/2}{\ln\left\lbrack \frac{\left( {2 + B_{3w}} \right)^{1/2} + \left( B_{3w} \right)^{1/2}}{\left( {2 + B_{3w}} \right)^{1/2} - \left( B_{3w} \right)^{1/2}} \right\rbrack}} - 1} \right\}.}}$LCB frequency (LCB_(Mi)), the number of LCB per 1000 C, of the i^(th)slice was then computed straightforwardly using the following equation(M_(i) is the MW of the i^(th) slice):LCB_(Mi)=1 000*14*B _(3w) /M _(i).The LCB distribution (LCBD) across the molecular weight distribution(MWD) was thus established for a full polymer.

Short chain branching distribution (SCBD) data was obtained using aSEC-FTIR high temperature heated flow cell (Polymer Laboratories) asdescribed by P. J. DesLauriers, D. C. Rohlfing, and E. T. Hsieh,Polymer, 43, 159 (2002).

Melt rheological characterizations were performed as follows.Small-strain (10%) oscillatory shear measurements were performed on aRheometrics Scientific, Inc. ARES rheometer using parallel-plategeometry. All rheological tests were performed at 190° C. The complexviscosity |η*| versus frequency (w) data were then curve fitted usingthe modified three parameter Carreau-Yasuda (CY) empirical model toobtain the zero shear viscosity—η₀, characteristic viscous relaxationtime—τ_(η), and the breadth parameter—a. The simplified Carreau-Yasuda(CY) empirical model is as follows.

${{{\eta^{*}(\omega)}} = \frac{\eta_{0}}{\left\lbrack {1 + \left( {\tau_{\eta}\omega} \right)^{a}} \right\rbrack^{{({1 - n})}/a}}},$wherein:

-   -   |η*(ω)|=magnitude of complex shear viscosity;    -   η₀=zero shear viscosity;    -   τ_(η)=viscous relaxation time;    -   a=“breadth” parameter;    -   n=fixes the final power law slope, fixed at 2/11; and    -   ω=angular frequency of oscillatory shearing deformation.

Details of the significance and interpretation of the CY model andderived parameters may be found in: C. A. Hieber and H. H. Chiang,Rheol. Acta, 28, 321 (1989); C. A. Hieber and H. H. Chiang, Polym. Eng.Sci., 32, 931 (1992); and R. B. Bird, R. C. Armstrong and O. Hasseger,Dynamics of Polymeric Liquids, Volume 1, Fluid Mechanics, 2nd Edition,John Wiley & Sons (1987); each of which is incorporated herein byreference in its entirety.

Nuclear Magnetic Resonance (NMR) spectra were obtained on a VarianMercury Plus 300 NMR spectrometer. CDCl₃ and C₆D₆ were purchased fromCambridge Isotope Laboratories, degassed and stored over activated 13×molecular sieves under nitrogen. NMR spectra were recorded using cappedor J. Young NMR tubes at ambient probe conditions. ¹H chemical shiftsare reported versus SiMe₄ and were determined by reference to theresidual ¹H and solvent peaks. Coupling constants are reported in Hz.

Gas chromatography was performed using a Varian 3800 GC analyzer fittedwith dual Factor Four all-purpose capillary columns (30 m×0.25 mm),flame ionization detector, and Varian 8400 autosampler unit. Massspectral analysis was performed in conjunction with a Varian 320 MSinstrument using electron ionization at 70 eV.

The sulfated alumina activator-support (abbreviated ACT1) employed insome of the examples was prepared in accordance with the followingprocedure. Bohemite was obtained from W.R. Grace Company under thedesignation “Alumina A” and having a surface area of about 300 m²/g anda pore volume of about 1.3 mL/g. This material was obtained as a powderhaving an average particle size of about 100 microns. This material wasimpregnated to incipient wetness with an aqueous solution of ammoniumsulfate to equal about 15% sulfate. This mixture was then placed in aflat pan and allowed to dry under vacuum at approximately 110° C. forabout 16 hours.

To calcine the support, about 10 grams of this powdered mixture wereplaced in a 1.75-inch quartz tube fitted with a sintered quartz disk atthe bottom. While the powder was supported on the disk, air (nitrogencan be substituted) dried by passing through a 13× molecular sievecolumn, was blown upward through the disk at the linear rate of about1.6 to 1.8 standard cubic feet per hour. An electric furnace around thequartz tube was then turned on and the temperature was raised at therate of about 400° C. per hour to the desired calcining temperature ofabout 600° C. At this temperature, the powder was allowed to fluidizefor about three hours in the dry air. Afterward, the sulfated aluminaactivator-support (ACT1) was collected and stored under dry nitrogen,and was used without exposure to the atmosphere.

The fluorided silica-alumina activator-support (abbreviated ACT2)employed in some of the examples was prepared in accordance with thefollowing procedure. A silica-alumina was obtained from W.R. GraceCompany containing about 13% alumina by weight and having a surface areaof about 400 m²/g and a pore volume of about 1.2 mL/g. This material wasobtained as a powder having an average particle size of about 70microns. Approximately 100 grams of this material were impregnated witha solution containing about 200 mL of water and about 10 grams ofammonium hydrogen fluoride, resulting in a damp powder having theconsistency of wet sand. This mixture was then placed in a flat pan andallowed to dry under vacuum at approximately 110° C. for about 16 hours.

To calcine the support, about 10 grams of this powdered mixture wereplaced in a 1.75-inch quartz tube fitted with a sintered quartz disk atthe bottom. While the powder was supported on the disk, air (nitrogencan be substituted) dried by passing through a 13× molecular sievecolumn, was blown upward through the disk at the linear rate of about1.6 to 1.8 standard cubic feet per hour. An electric furnace around thequartz tube was then turned on and the temperature was raised at therate of about 400° C. per hour to the desired calcining temperature ofabout 450° C. At this temperature, the powder was allowed to fluidizefor about three hours in the dry air. Afterward, the fluoridedsilica-alumina activator-support (ACT2) was collected and stored underdry nitrogen, and was used without exposure to the atmosphere.

The fluorided silica-alumina activator-support (abbreviated ACT4)employed in some of the examples was prepared in accordance with thefollowing procedure. A silica-coated alumina was obtained from SasolCompany under the designation “Siral 28M” containing about 72% aluminaby weight, and having a surface area of about 340 m²/g, a pore volume ofabout 1.6 mL/g, and an average particle size of about 90 microns. About20 g of the Siral 28M was first calcined at about 600° C. forapproximately 8 hours, then impregnated to incipient wetness with 60 mLof a methanol solution containing 2 g of ammonium bifluoride. Thismixture was then placed in a flat pan and allowed to dry under vacuum atapproximately 110° C. for about 12 hours.

To calcine the support, the powdered mixture was placed in a 2-inch bedfluidized by dry nitrogen. The temperature was ramped up to 600° C. overa period of 1.5 hours, and then held at 600° C. for three hours.Afterward, the fluorided silica-coated alumina (ACT4) was collected andstored under dry nitrogen, and was used without exposure to theatmosphere.

The titanated fluorided silica-alumina activator-support (abbreviatedACT3) employed in some of the examples was prepared in accordance withthe following procedure. A silica-coated alumina was obtained from SasolCompany under the designation “Siral 28M” containing about 72% aluminaby weight, and having a surface area of about 340 m²/g, a pore volume ofabout 1.6 mL/g, and an average particle size of about 90 microns. About682 g of the Siral 28M was first calcined at about 600° C. forapproximately 8 hours, then impregnated to incipient wetness with 2200mL of a methanol solution containing 147 g of a solution containing 60%H₂TiF₆. This mixture, with the consistency of wet sand, was then placedin a flat pan and allowed to dry under vacuum at approximately 110° C.for about 12 hours.

To calcine the support, the powdered mixture was placed in a 2-inch bedfluidized by dry nitrogen. The temperature was ramped up to 600° C. overa period of 1.5 hours, and then held at 600° C. for three hours.Afterward, the titanated fluorided silica-coated alumina (ACT3) wascollected and stored under dry nitrogen, and was used without exposureto the atmosphere.

The polymerization runs were conducted in a one-gallon (3.8-liter)stainless steel reactor as follows. First, the reactor was purged withnitrogen and then with isobutane vapor. Approximately 0.5 mL of a 1Msolution in heptane of either triisobutylaluminum (TIBA) ortriethylaluminum (TEA), the activator-support (ACT1, ACT2, ACT3, orACT4), and the metallocene (MET1, MET2, or MET3; structures providedbelow) were added through a charge port while venting isobutane vapor.The charge port was closed and about 2 L of isobutane were added. Theresulting mixture was stirred for 5 min, and then heated to the desiredpolymerization temperature. Upon approaching the polymerization reactortemperature, ethylene was charged to the reactor to achieve the desiredtotal reactor pressure, along with a desired amount of 1-hexenecomonomer (if used). Ethylene was fed on demand as the polymerizationreaction proceeded to maintain constant reactor pressure. If used,hydrogen was added at a fixed mass ratio with respect to the ethyleneflow. The reactor was maintained and controlled at the desiredtemperature and reactor pressure throughout the 60 min run time of thepolymerization. Upon completion, the isobutane and ethylene were ventedfrom the reactor, the reactor was opened and cooled, and the polymerproduct was collected and dried.

Examples 1-99 Polymers Produced Using an Ansa-Metallocene Having Formula(I)

Metallocene compounds used in these examples had the followingstructures and abbreviations:

Synthesis of MET1:

A solution of 1,2-dichloro-1,1,2,2-tetramethyldisilane (2.29 g, 12.3mmol) in Et₂O (25 mL) was prepared. A solution of Li(allyl-indenyl)(1.00 g, 6.17 mmol) in Et₂O (25 mL) was prepared and added dropwise bycannula to the stirred disilane solution at approximately 22° C. over 1hr. The mixture was stirred overnight and evaporated under vacuum. Theresidue was suspended in toluene (20 mL), filtered through a pad ofCelite and an aliquot of the filtrate was removed. NMR analysis showedthe presence of Me₄Si₂(allyl-indenyl)Cl and starting disilane. ¹H NMRdata for Me₄Si₂(allyl-indenyl)Cl (C₆D₆): δ 7.31 (d, J=8, 2H, C₆-Ind),7.19 (t, J=8, 1H, C₆-Ind), 7.08 (t, J=8, 1H, C₆-Ind), 6.22 (m, 1H,C₅-Ind), 5.96 (m, 1H, CH═CH₂), 5.14 (m, 1H, CH═CH₂), 5.06 (m, 1H,CH═CH₂), 3.30 (m, C₅-Ind), 3.20 (m, 2H, CH₂), 0.21 (s, 3H, SiMe), 0.15(s, 3H, SiMe), 0.12 (s, 3H, SiMe), −0.09 (s, 3H, SiMe). The filtrate wasevaporated and dried under vacuum overnight to obtain a yellow oil (1.9g). THF (20 mL) was added by cannula, and a solution ofcyclopentadienyl-MgCl (7.0 mL, 1.0 M in THF, 7.0 mmol) was addeddropwise by syringe to the stirred solution at approximately 22° C. over15 min. The mixture was stirred for 2 hr and an aliquot was removed bysyringe. GC-MS analysis showed about 95% conversion to the expectedligand Me₄Si₂(allyl-indenyl)(cyclopentadienyl) (m/z, 337 {M⁺}), with thebalance comprised of products derived from the starting materials. Themixture was stirred an additional 1 hr and evaporated under vacuum. Theresidue was dried under vacuum at 35° C. for 1 hr and toluene (20 mL)was added. The suspension was filtered through a pad of Celite and theCelite was washed with toluene (2×20 mL). The toluene solutions werecombined and evaporated under vacuum to obtain a yellow oil (2.05 g).Et₂O (50 mL) was added and the resulting solution was cooled in an icewater bath. A solution of n-BuLi (5.1 mL, 2.5 M in hexanes, 13 mmol) wasadded by syringe over 3 min and the stirred mixture was warmed to roomtemperature over 30 min. A suspension of ZrCl₄ (1.49 g, 6.39 mmol) inheptane (50 mL) was prepared and cooled in an ice water bath. Thelithium solution was added dropwise by cannula to the stirred zirconiumsuspension over 30 min, and the mixture was stirred in the bathovernight. The bright yellow slurry was evaporated under vacuum andCH₂Cl₂ (50 mL) was added by cannula. The suspension was filtered througha pad of Celite and the Celite was washed with CH₂Cl₂ (2×20 mL). Theresulting solutions were combined and evaporated under vacuum to obtaina dark yellow solid (2.76 g). The residue was recrystallized fromtoluene (10 mL) at −30° C. to obtain MET1 as a yellow crystalline solid,which was dried under vacuum (900 mg, 29% recrystallized yield based onLi(allyl-indenyl). ¹H NMR (CDCl₃): δ 7.73 (d, J=8, 1H, C₆-Ind), 7.63 (d,J=8, 1H, C₆-Ind), 7.32 (t, J=8, 1H, C₆-Ind), 7.24 (t, J=8, 1H, C₆-Ind),6.73 (m, 1H, Cp), 6.72 (s, 1H, C₅-Ind), 6.41 (m, 1H, Cp), 6.18 (m, 1H,Cp), 6.13 (m, 1H, Cp), 6.01 (m, 1H, CH═CH₂), 5.16 (m, 1H, CH═CH₂), 5.11(m, 1H, CH═CH₂), 3.72 (d, J=7, 2H, CH₂), 0.62 (s, 3H, SiMe), 0.58 (s,3H, SiMe), 0.55 (s, 3H, SiMe), 0.52 (s, 3H, SiMe).

Synthesis of MET2:

A solution of indene (10.0 mL, 86.1 mmol) in Et₂O (200 mL) was preparedand cooled in dry ice/acetone. A solution of n-BuLi (34.5 mL, 2.5 M, 86mmol) was added by syringe over 3 min. The bath was removed and themixture was stirred for 4 hr, and then cooled again in dry ice/acetone.Neat 1-bromo-3-phenylpropane (13.1 mL, 86.1 mmol) was added by syringeover 1 min and the stirred mixture was slowly warmed out of the bath toapproximately 22° C. overnight. The mixture was slowly quenched withwater (5 mL) and then additional water (50 mL) was added. The biphasicmixture was shaken, the organic layer was separated, dried over MgSO₄,filtered and evaporated under vacuum to obtain(3-phenylpropyl)-1H-indene as a yellow oil (18.61 g, 95 mol % puritybased on GC analysis). GC-MS: m/z, 234 (M⁺). A solution of(3-phenylpropyl)-1H-indene (3.00 g, 12.8 mmol) in Et₂O (50 mL) wasprepared and cooled in an ice water bath. A solution of n-BuLi (5.1 mL,2.5 M, 13 mmol) was added by syringe over 30 sec, the bath was removedand the mixture was stirred for 1.5 hr. A solution of Me₄Si₂Cl₂ (4.92 g,26.2 mmol) in Et₂O (25 mL) was prepared and the Li(indenyl) solution wasadded dropwise by cannula to the stirred disilane solution atapproximately 22° C. over 1 hr. The mixture was stirred overnight, andthen evaporated and dried under vacuum for 4 hr to obtain a yellow oil.THF (50 mL) was added by cannula and a solution of cyclopentadienyl-MgCl(14.0 mL, 1.0 M in THF, 14 mmol) was added to the stirred solution bysyringe over 5 min. The mixture was stirred overnight, evaporated undervacuum, triturated with toluene (20 mL), allowed to settle, and thesupernatant decanted. The trituration procedure was repeated and thetoluene solutions were combined and evaporated under vacuum to obtain anorange oil (4.11 g). Et₂O (75 mL) was added by cannula, and theresulting mixture was cooled in an ice bath. A solution of n-BuLi (8.1mL, 2.5 M in hexanes, 20 mmol) was added by syringe over 1 min to obtaina fine suspension. The bath was removed and the stirred suspension waswarmed to approximately 22° C. over 2 hr. THF (1.6 mL) was added bysyringe. A suspension of ZrCl₄ (2.37 g, 10.2 mmol) in heptane (75 mL)was prepared and cooled in an ice water bath. The lithium solution wasadded dropwise by cannula to the stirred zirconium suspension over 20min, and the mixture was warmed to approximately 22° C. overnight. Thevolatiles were removed under vacuum and CH₂Cl₂ (100 mL) was added bycannula. The suspension was filtered through a pad of Celite and theCelite was washed with CH₂Cl₂ (2×20 mL). The filtrate and washes werecombined and evaporated under vacuum to obtain a dark yellow solid (5.79g). The residue was triturated in 1/1 toluene/heptane (20 mL) at storedat −30° C. to precipitate impurities. The supernatant was decanted andevaporated under vacuum, and the trituration procedure was repeated. Thesupernatant was decanted and evaporated to obtain MET2 as an orange oil(3.03 g).

Synthesis of MET3:

Portions of the following synthesis procedure were based on a methoddescribed in the Journal of Organometallic Chemistry, 1999, 585, 18-25,the disclosure of which is incorporated herein by reference in itsentirety. A solution of indene (95 mole percent purity, 10 mL, 81.8mmol) in Et₂O (200 mL) was prepared, cooled in dry ice/acetone, andcharged with a solution of n-BuLi (33 mL, 2.5 M in hexanes, 83 mmol) bysyringe over 1 min. The solution was stirred and allowed to warm slowlyto approximately 22° C. over 16 hr. A separate solution of1,2-dichloro-1,1,2,2-tetramethyldisilane (7.54 g, 40.3 mmol) in Et₂O(100 mL) was prepared and cooled in ice water. The prepared Li-Indsolution was added dropwise by cannula to the disilane solution over 1hr. The resulting pale-yellow suspension was stirred and warmed slowlyto approximately 22° C. over 16 hr. The solution was evaporated undervacuum resulting in a beige solid. Toluene (75 mL) was added by cannulaand the resulting suspension was centrifuged. The supernatant solutionwas removed by cannula, and this toluene extraction procedure wasrepeated to produce two toluene extracts. The two extracts were combinedand evaporated to a volume of approximately 75 mL. The resultingsuspension was warmed to 40° C. in a hot water bath, and stirred todissolve the precipitated solid. The stirring was halted upon completedissolution of the solid, and then the solution was allowed to coolslowly to approximately 22° C. for about 16 hours. The supernatantsolution was decanted by cannula and the resulting precipitate was driedunder vacuum to obtainrac/meso-1,2-bis(inden-1-yl)-1,1,2,2-tetramethyldisilane as an amber,crystalline solid (5.55 g). The supernatant solution was concentratedand a recrystallization procedure analogous to the aforementioned wasrepeated twice to obtain two additional amounts of the rac/meso-bridgedligand (2.83 g and 1.52 g, respectively) exhibiting comparable NMRpurity to that of the first. Total isolated yield ofrac/meso-1,2-bis(inden-1-yl)-1,1,2,2-tetramethyldisilane was 9.90 g,71%. ¹H NMR data indicated the presence of a 2/1 mixture ofdiastereomers, neither of which could be unambiguously characterized asrac or meso due to the presence of symmetry elements in both cases. Key¹H NMR data for the major isomer (CDCl₃): δ 6.28 (dd, J=5, 2; 2H,C₅-Ind), 3.16 (s, 2H, C₅-Ind), −0.18 (s, 6H, SiMe₂), −0.30 (s, 6H,SiMe₂). Key ¹H NMR data for the minor isomer (CDCl₃): δ 6.42 (dd, J=5,2; 2H, C₅-Ind), 3.27 (s, 2H, C₅-Ind), −0.10 (s, 6H, SiMe₂), −0.45 (s,6H, SiMe₂). A solution ofrac/meso-1,2-bis(inden-1-yl)-1,1,2,2-tetramethyldisilane (2.82 g, 8.14mmol) in Et₂O (75 mL) was prepared, cooled to −5° C., and charged with asolution of n-BuLi (6.7 mL, 2.5 M in hexanes, 17 mmol) by syringe over30 sec. The mixture was stirred for 10 min, and then allowed to warm toapproximately 22° C. over 16 hr while stirring. A suspension of ZrCl₄(1.90 g, 8.14 mmol) in toluene (50 mL) was prepared and cooled to −5° C.The lithiated bis(indenide) solution obtained from the rac/meso-bridgedligand was added to the stirred zirconium suspension by cannula over 30sec. The cooling bath was removed and the resulting yellow-orangesuspension was stirred and warmed to approximately 22° C. over 16 hr.The yellow suspension was evaporated under vacuum and toluene (50 mL)was added by cannula. The suspension was centrifuged, and thesupernatant solution was removed by cannula and evaporated under vacuumat 40° C. to obtain rac/meso-MET3 (1:1 rac/meso) as a yellow solid. Thesolid was recrystallized twice from toluene to obtain pure meso-MET3.NMR data for these samples in CDCl₃ solution matched those reported inthe Journal of Organometallic Chemistry, 1999, 585, 18-25, for the MET3compound.

Polymerization Experiments:

The polymerization conditions and the resultant polymer properties forExamples 1-99 are summarized in Table I. Any listing of MET3 in Table Iis meant to indicate the meso isomer of MET3, i.e., meso-MET3. The H₂feed in ethylene is listed in ppm on a weight basis (ppmw). Applicantsbelieve that a quality issue with the batch of co-catalyst used inExamples 91-93 may have adversely affected the catalyst activity and thepolymer properties of these examples.

FIG. 1 illustrates the molecular weight distributions of the polymers ofExamples 3, 5, and 7. For the copolymers of these examples, FIG. 1demonstrates that Mw was substantially constant over a range of amountsof added hydrogen.

FIG. 2 illustrates the molecular weight distributions of the polymers ofExamples 2, 6, and 15. For the homopolymers of these examples, FIG. 2demonstrates that Mw decreased as the amount of added hydrogenincreased.

FIG. 3 illustrates the molecular weight distributions of the polymers ofExamples 2-3 and 16. For the polymers of these examples, FIG. 3demonstrates that Mw/Mn increased as comonomer content increased, in theabsence of added hydrogen.

FIG. 4 illustrates the molecular weight distributions of the polymers ofExamples 6-7 and 44-45 at 250 ppm added hydrogen. FIG. 4 demonstratesthat the Mw and the Mw/Mn of the copolymers were significantly greaterthan that of the homopolymer.

FIG. 5 illustrates the radius of gyration versus the logarithm of themolecular weight for a linear standard and the polymers of Examples 2-3and 6-7, with data from SEC-MALS. FIG. 5 demonstrates these polymerswere substantially linear polymers with minimal amounts of LCB's (longchain branches).

FIG. 6 illustrates the Delta versus the log G* (complex modulus) for thepolymers of Examples 2-3 and 6-7. Similar to FIG. 5, the rheology datain FIG. 6 demonstrates that these polymers were substantially linear.

FIG. 7 illustrates the catalyst activity versus initial 1-hexenecomonomer concentration for Examples 2-7 and 40-45 at varying amounts ofadded hydrogen. FIG. 7 demonstrates that the catalyst activities forthese examples were substantially constant at a given comonomerconcentration, even when hydrogen was added. Additionally, FIG. 7demonstrates that the catalyst activity generally decreased as comonomercontent increased.

FIG. 8 illustrates plots of first order models of catalyst activityversus initial 1-hexene comonomer concentration for Examples 2-7 and40-45. FIG. 8 demonstrates that the catalyst activities (abbreviated A)of these examples varied uniformly with comonomer concentration(1-hexene) at a given hydrogen content, following the first orderexponential profile of (eq.1) below, where k is the slope.

$\begin{matrix}{{\ln\left( \frac{A - A_{\infty}}{A_{0} - A_{\infty}} \right)} = {- {kC}_{hexene}}} & \left( {{eq}.\mspace{14mu} 1} \right)\end{matrix}$

FIG. 9 illustrates plots of the logarithm of melt index versus thelogarithm of the hydrogen feed concentration (hydrogen/ethylene) for thepolymers of Examples 4-5, 7, and 17-24. FIG. 9 demonstrates thedifference in hydrogen response when a copolymer was being produced ascompared to when a homopolymer was being produced.

FIG. 10 illustrates a plot of the high load melt index versus the meltindex for the polymers of Examples 4 and 17-24. FIG. 10 demonstratesthat the shear rate ratio (HLMI/MI) was substantially constant across arange of hydrogen concentrations under homopolymer conditions.

FIG. 11 illustrates a plot of zero shear viscosity versus weight-averagemolecular weight, specifically, log(η₀) versus log(Mw), for the polymersof Examples 2-3, 5-7, 18, 44-45, and 66-67. FIG. 11 demonstrates the lowlevels of long chain branches (LCB's) attainable with this invention.Linear polyethylene polymers are observed to follow a power lawrelationship between their zero shear viscosity, η₀, and theirweight-average molecular weight, Mw, with a power very close to 3.4.This relationship is shown by a straight line with a slope of 3.4 whenthe logarithm of η₀ is plotted versus the logarithm of Mw (labeledLinear PE in FIG. 11). Deviations from this linear polymer line aregenerally accepted as being caused by the presence of LCB's. Janzen andColby presented a model that predicts the expected deviation from thelinear plot of log(η₀) vs. log(Mw) for given amounts of LCB content as afunction of the Mw of the polymer. See “Diagnosing long-chain branchingin polyethylenes,” J. Mol. Struct. 485-486, 569-584 (1999), which isincorporated herein by reference in its entirety. The polymers ofExamples 2-3, 5-7, 18, 44-45, and 66-67 deviated only slightly from thewell-known 3.4 power law “Arnett line” which is used as an indication ofa linear polymer (J. Phys. Chem. 1980, 84, 649). All of these polymershad levels of LCB's at or below the line representing 1×10⁻⁶ LCB's percarbon atom, which is equivalent to 0.001 LCB per 1000 total carbonatoms.

TABLE I Polymerization Conditions and Polymer Properties for Examples1-99. H2 Feed 1- Co- Reactor in 1- hexene/ PE Catalyst Activator ExampleCatalyst Catalyst Activator Activator catalyst Temp Pressure Ethylenehexene ethylene Yield Activity Activity No Type Wt (mg) Type Wt (mg)Type (deg C.) (psig) (ppmw) (g) (mol/mol) (g) (g/μmol/h) (g/g/hr) 1 MET13.4 ACT1 200 TIBA 90 450 0 0 0.00 404 59.0 2020 2 MET1 3.4 ACT1 200 TIBA90 390 0 0 0.00 264 38.6 1320 3 MET1 3.4 ACT1 200 TIBA 90 390 0 30 0.20160 23.4 800 4 MET1 3.4 ACT1 200 TIBA 90 390 125 0 0.00 325 47.5 1625 5MET1 3.4 ACT1 200 TIBA 90 390 125 30 0.20 162 23.7 810 6 MET1 3.4 ACT1200 TIBA 90 390 250 0 0.00 224 32.7 1120 7 MET1 3.4 ACT1 200 TIBA 90 390250 30 0.20 150 21.9 750 8 MET1 3.4 ACT1 200 TIBA 90 390 0 0 0.00 28842.1 1440 9 MET1 3.4 ACT2 200 TIBA 90 390 0 0 0.00 17.4 2.5 87 10 MET13.4 ACT1 200 TEA 90 390 0 0 0.00 127 18.6 635 11 MET1 1.7 ACT1 200 TIBA90 390 0 0 0.00 180 52.6 900 12 MET1 1.7 ACT1 100 TIBA 90 390 0 0 0.00115 33.6 1150 13 MET1 3.4 ACT1 200 TIBA 85 362 0 0 0.00 260 38.0 1300 14MET1 3.4 ACT1 200 TIBA 95 420 0 0 0.00 300 43.8 1500 15 MET1 3.4 ACT1200 TIBA 90 390 500 0 0.00 130 19.0 650 16 MET1 3.4 ACT1 200 TIBA 90 3900 50 0.32 137 20.0 685 17 MET1 3.4 ACT1 200 TIBA 90 390 170 0 0.00 29743.4 1485 18 MET1 3.4 ACT1 200 TIBA 90 390 185 0 0.00 245 35.8 1225 19MET1 3.4 ACT1 200 TIBA 90 390 200 0 0.00 205 30.0 1025 20 MET1 3.4 ACT1200 TIBA 90 390 215 0 0.00 235 34.3 1175 21 MET1 3.4 ACT1 200 TIBA 90390 230 0 0.00 195 28.5 975 22 MET1 3.4 ACT1 200 TIBA 90 390 245 0 0.00200 29.2 1000 23 MET1 3.4 ACT1 200 TIBA 90 390 260 0 0.00 180 26.3 90024 MET1 3.4 ACT1 200 TIBA 90 390 275 0 0.00 167 24.4 835 25 MET1 3.4ACT1 200 TIBA 100 448 0 0 0.00 258 37.7 1290 26 MET1 3.4 ACT1 200 TIBA80 335 0 0 0.00 240 35.1 1200 27 MET1 3.4 ACT1 200 TIBA 80 335 0 0 0.00225 32.9 1125 28 MET1 3.4 ACT1 200 TIBA 90 390 60 0 0.00 205 30.0 102529 MET1 3.4 ACT1 200 TIBA 90 390 300 0 0.00 215 31.4 1075 30 MET1 3.4ACT1 200 TIBA 90 390 0 10 0.07 185 27.0 925 31 MET1 3.4 ACT1 200 TIBA 90390 0 20 0.14 160 23.4 800 32 MET1 3.4 ACT1 200 TIBA 90 390 125 10 0.07180 26.3 900 33 MET1 3.4 ACT1 200 TIBA 80 335 185 0 0.00 268 39.2 134034 MET1 3.4 ACT1 200 TIBA 85 362 185 0 0.00 252 36.8 1260 35 MET1 3.4ACT1 200 TIBA 90 390 185 0 0.00 257 37.5 1285 36 MET1 3.4 ACT1 200 TIBA95 420 185 0 0.00 235 34.3 1175 37 MET1 3.4 ACT1 200 TIBA 100 448 185 00.00 170 24.8 850 38 MET1 3.4 ACT1 200 TIBA 90 390 60 0 0.00 235 34.31175 39 MET1 3.4 ACT1 200 TIBA 90 390 300 0 0.00 233 34.0 1165 40 MET13.4 ACT1 200 TIBA 90 390 0 10 0.07 180 26.3 900 41 MET1 3.4 ACT1 200TIBA 90 390 0 20 0.14 167 24.4 835 42 MET1 3.4 ACT1 200 TIBA 90 390 12510 0.07 190 27.8 950 43 MET1 3.4 ACT1 200 TIBA 90 390 125 20 0.14 16524.1 825 44 MET1 3.4 ACT1 200 TIBA 90 390 250 10 0.07 175 25.6 875 45MET1 3.4 ACT1 200 TIBA 90 390 250 20 0.14 157 22.9 785 46 MET1 3.4 ACT1200 TIBA 90 390 185 10 0.07 155 22.6 775 47 MET1 3.4 ACT1 200 TIBA 90390 185 20 0.14 160 23.4 800 48 MET1 3.4 ACT1 200 TIBA 90 390 185 300.20 142 20.7 710 49 MET1 3.4 ACT1 200 TIBA 90 390 250 10 0.07 175 25.6875 50 MET2 4.0 ACT1 200 TIBA 90 450 0 0 0.00 342 49.1 1710 51 MET2 4.0ACT1 200 TIBA 90 450 0 0 0.00 340 48.9 1700 52 MET2 4.0 ACT2 200 TIBA 90450 0 0 0.00 32 4.6 160 53 MET2 4.0 ACT1 200 TEA 90 450 0 0 0.00 16523.7 825 54 MET2 4.0 ACT1 200 TIBA 90 390 0 0 0.00 175 25.1 875 55 MET24.0 ACT1 200 TIBA 90 390 0 0 0.00 260 37.4 1300 56 MET2 2.0 ACT1 200TIBA 90 390 0 0 0.00 185 53.2 925 57 MET2 2.0 ACT1 100 TIBA 90 390 0 00.00 125 35.9 1250 58 MET2 4.0 ACT3 200 TIBA 90 390 0 0 0.00 330 47.41650 59 MET2 2.0 ACT3 200 TIBA 90 390 0 0 0.00 330 94.9 1650 60 MET2 1.0ACT3 200 TIBA 90 390 0 0 0.00 280 161.0 1400 61 MET2 0.5 ACT3 200 TIBA90 390 0 0 0.00 180 206.9 900 62 MET2 1.0 ACT3 200 TIBA 90 390 300 00.00 242 139.1 1210 63 MET1 4.0 ACT3 200 TIBA 90 390 0 0 0.00 420 52.22100 64 MET1 2.0 ACT3 200 TIBA 90 390 0 0 0.00 240 59.6 1200 65 MET1 1.0ACT3 200 TIBA 90 390 0 0 0.00 200 99.3 1000 66 MET1 0.5 ACT3 200 TIBA 90390 0 0 0.00 140 139.1 700 67 MET1 0.5 ACT3 200 TIBA 90 390 190 0 0.00215 213.6 1075 68 MET1 0.5 ACT3 200 TIBA 80 335 0 0 0.00 215 213.6 107569 MET1 0.5 ACT3 200 TIBA 85 362 0 0 0.00 180 178.8 900 70 MET1 0.5 ACT3200 TIBA 90 390 0 0 0.00 195 193.7 975 71 MET1 0.5 ACT3 200 TIBA 95 4200 0 0.00 225 223.5 1125 72 MET1 0.5 ACT3 200 TIBA 100 448 0 0 0.00 210208.6 1050 73 MET2 1.0 ACT3 200 TIBA 90 390 300 0 0.00 240 138.0 1200 74MET2 1.0 ACT3 200 TIBA 90 390 325 0 0.00 176 101.2 880 75 MET2 1.0 ACT3200 TIBA 90 390 350 0 0.00 182 104.6 910 76 MET2 1.0 ACT3 200 TIBA 90390 375 0 0.00 170 97.7 850 77 MET2 1.0 ACT3 200 TIBA 90 390 400 0 0.00154 88.5 770 78 MET2 1.0 ACT3 200 TIBA 90 390 300 10 0.07 235 135.1 117579 MET2 1.0 ACT3 200 TIBA 90 390 325 10 0.07 180 103.5 900 80 MET2 1.0ACT3 200 TIBA 90 390 350 10 0.07 185 106.3 925 81 MET2 1.0 ACT3 200 TIBA90 390 375 10 0.07 150 86.2 750 82 MET2 1.0 ACT3 200 TIBA 90 390 400 100.07 176 101.2 880 83 MET1 3.4 ACT1 200 TIBA 90 390 185 0 0.00 312 45.61560 84 MET1 3.4 ACT1 200 TIBA 90 390 190 0 0.00 272 39.7 1360 85 MET13.4 ACT1 200 TIBA 90 390 190 0 0.00 214 31.3 1070 86 MET3 1.7 ACT1 200TIBA 90 390 0 0 0.00 150 44.7 750 87 MET1 3.4 ACT1 200 TIBA 90 390 190 00.00 260 38.0 1300 88 MET3 1.7 ACT1 200 TIBA 90 390 100 0 0.00 191 56.9955 89 MET3 1.7 ACT1 200 TIBA 90 390 250 0 0.00 235 70.0 1175 90 MET31.7 ACT1 200 TIBA 90 390 500 0 0.00 100 29.8 500 91 MET3 1.7 ACT1 200TIBA 90 390 100 30 0.20 120 35.8 600 92 MET3 1.7 ACT1 200 TIBA 90 390250 30 0.20 180 53.7 900 93 MET3 1.7 ACT1 200 TIBA 90 390 500 30 0.20192 57.2 960 94 MET3 1.7 ACT1 200 TIBA 90 390 500 30 0.21 291 86.9 145595 MET3 1.7 ACT1 200 TIBA 90 390 500 0 0.00 155 46.3 775 96 MET3 1.7ACT1 200 TIBA 90 390 0 0 0.00 230 68.7 1150 97 MET3 1.7 ACT1 200 TIBA 90390 0 0 0.00 166 49.6 830 98 MET3 1.7 ACT1 200 TIBA 90 390 250 10 0.07412 123.0 2060 99 MET3 1.7 ACT4 200 TIBA 90 390 250 10 0.07 176 52.5 880MI Example (g/10 HLMI HLMI/ Density Mn Mw Mz Mw/ Mz/ SCB/1000 No min)(g/10 min) MI (g/cc) (kg/mol) (kg/mol) (kg/mol) Mn Mw η₀ τ_(η) a Carbons1 0.000 0.000 — — 192.9 462.7 978.5 2.40 2.11 — — — — 2 0.000 0.000 —0.9378 257.6 547.2 959.9 2.12 1.75 1883000 0.8807 0.4268 0.86 3 0.0000.222 — 0.9269 162.9 396.0 676.4 2.43 1.71 505800 0.2626 0.4394 2.95 40.040 1.310 32.75 — — — — — — — — — — 5 0.018 0.730 40.56 — 45.1 286.7567.8 6.35 1.98 197300 0.1485 0.4469 — 6 9.960 186.600 18.73 0.9671 20.171.6 153.7 3.56 2.15 720 0.0014 0.6335 0.83 7 0.030 0.950 31.67 0.935437.0 283.9 582.3 7.67 2.05 159900 0.1264 0.4486 2.38 8 0.000 0.050 — —245.7 543.2 943.2 2.21 1.74 — — — — 9 0.000 0.054 — — 214.7 586.8 1219.12.73 2.08 — — — — 10 0.000 0.069 — — — — — — — — — — — 11 0.000 0.030 —— — — — — — — — — — 12 0.000 0.030 — — — — — — — — — — — 13 0.000 0.040— — — — — — — — — — — 14 0.000 0.067 — — 234.7 503.7 847.1 2.15 1.68 — —— — 15 148.500 836.000 5.63 — 8.8 33.1 70.1 3.74 2.12 — — — — 16 0.0170.346 20.35 — 108.8 337.9 598.9 3.11 1.77 — — — — 17 1.140 26.400 23.16— — — — — — — — — — 18 0.900 18.600 20.67 — 26.8 136.7 330.7 5.10 2.429567 0.0210 0.5045 — 19 2.060 38.800 18.83 — — — — — — — — — — 20 3.50070.400 20.11 — — — — — — — — — — 21 8.150 159.400 19.56 — — — — — — — —— — 22 10.300 202.600 19.67 — — — — — — — — — — 23 18.300 320.000 17.49— — — — — — — — — — 24 20.100 364.000 18.11 — — — — — — — — — — 25 0.0000.140 — — — — — — — — — — — 26 0.000 0.000 — — — — — — — — — — — 274.020 90.700 22.56 — — — — — — — — — — 28 0.000 0.000 — — — — — — — — —— — 29 0.000 0.000 — — — — — — — — — — — 30 0.000 0.000 — — — — — — — —— — — 31 0.000 0.000 — — — — — — — — — — — 32 0.000 0.000 — — — — — — —— — — — 33 0.710 17.300 24.37 — — — — — — — — — — 34 0.840 20.600 24.52— — — — — — — — — — 35 0.960 21.700 22.60 — — — — — — — — — — 36 0.4009.030 22.58 — — — — — — — — — — 37 0.053 1.640 30.94 — — — — — — — — — —38 0.000 0.220 22000.00 — — — — — — — — — — 39 13.100 46.700 3.56 — — —— — — — — — — 40 0.000 0.120 12000.00 — — — — — — — — — — 41 0.000 018000.00 — — — — — — — — — — 42 0.000 0.310 31000.00 — — — — — — — — — —43 0.012 0.730 60.83 — — — — — — — — — — 44 0.005 0.490 98.00 — 49.1319.6 632.7 6.51 1.98 274500 0.1960 0.4470 — 45 0.029 0.930 32.07 — 42.7279.5 577.8 6.54 2.07 169700 0.1383 0.4478 — 46 0.022 0.790 35.91 — — —— — — — — — — 47 0.000 0.000 — — — — — — — — — — — 48 0.000 0.000 — — —— — — — — — — — 49 0.000 0.000 — — — — — — — — — — — 50 0.000 0.000 — —— — — — — — — — — 51 0.000 0.000 — — — — — — — — — — — 52 0.000 0.000 —— — — — — — — — — — 53 0.000 0.000 — — — — — — — — — — — 54 0.000 0.000— — — — — — — — — — — 55 0.000 0.000 — — — — — — — — — — — 56 0.0000.000 — — — — — — — — — — — 57 0.000 0.000 — — — — — — — — — — — 580.000 0.000 — — — — — — — — — — — 59 0.000 0.000 — — — — — — — — — — —60 0.000 0.000 — — — — — — — — — — — 61 0.000 0.000 — — — — — — — — — —— 62 0.630 30.500 48.41 — 23.0 146.8 1569.8 6.39 10.70 2694000 0.00000080.0564 — 63 0.000 0.170 — — — — — — — — — — — 64 0.000 0.520 — — — — — —— — — — — 65 0.000 0.000 — — — — — — — — — — — 66 0.000 0.000 — — 266.1605.2 1368.9 2.27 2.26 5674000 2.5790 0.3349 — 67 0.000 0.042 — — 216.6570.5 1433.3 2.63 2.51 2877000 1.4030 0.3856 — 68 0.000 0.000 — — — — —— — — — — — 69 0.000 0.000 — — — — — — — — — — — 70 0.000 0.000 — — — —— — — — — — — 71 0.000 0.000 — — — — — — — — — — — 72 0.000 0.000 — — —— — — — — — — — 73 0.042 6.600 157.14 — — — — — — — — — — 74 0.05433.500 620.37 — — — — — — — — — — 75 0.640 53.500 83.59 — — — — — — — —— — 76 0.790 50.700 64.18 — — — — — — — — — — 77 0.620 56.000 90.32 — —— — — — — — — — 78 0.018 0.910 50.56 — — — — — — — — — — 79 0.000 0.000— — — — — — — — — — — 80 0.000 0.000 — — — — — — — — — — — 81 0.0000.000 — — — — — — — — — — — 82 0.000 0.000 — — — — — — — — — — — 830.270 8.170 30.26 — — — — — — — — — — 84 0.025 0.980 39.68 — — — — — — —— — — 85 0.000 0.165 1650.00 — — — — — — — — — — 86 0.107 3.640 34.02 —22.4 211.7 587.4 9.45 2.78 — — — — 87 0.660 17.700 26.82 — — — — — — — —— — 88 0.079 2.610 33.04 — 40.2 225.9 568.0 5.62 2.51 — — — — 89 2.83078.050 27.58 — 15.5 99.0 291.3 6.37 2.94 — — — — 90 35.300 833.000 23.60— 6.7 48.7 157.2 7.26 3.22 — — — — 91 0.280 7.780 27.79 — 19.1 171.6430.4 8.96 2.51 — — — — 92 0.335 9.380 28.00 — 29.3 162.6 418.7 5.562.57 — — — — 93 0.870 22.900 26.32 — 21.3 129.8 342.1 6.08 2.64 — — — —94 5.910 191.0 32.31 — 11.4 80.0 256.7 6.99 3.21 — — — — 95 39.600 833.021.04 — 7.7 48.9 158.2 6.40 3.23 — — — — 96 0.064 2.9 45.94 — 33.0 235.2603.6 7.13 2.57 — — — — 97 — — — — — — — — — — — — — 98 — — — — — — — —— — — — — 99 — — — — — — — — — — — — —

We claim:
 1. An olefin polymerization process, the process comprising:contacting a catalyst composition with an olefin monomer and optionallyan olefin comonomer under polymerization conditions to produce an olefinpolymer having less than about 0.002 long chain branches per 1000 totalcarbon atoms, wherein the catalyst composition comprises: (i) anactivator; and (ii) an ansa-metallocene compound having formula (I):E(Cp^(A)R^(A) _(m))(Cp^(B)R^(B) _(n))MX_(q)  (I), wherein: M is Ti, Zr,Hf, Cr, Sc, Y, La, or a lanthanide; Cp^(A) and Cp^(B) independently area cyclopentadienyl, indenyl, or fluorenyl group; each R^(A) and R^(B)independently is H or a hydrocarbyl, hydrocarbylsilyl, hydrocarbylamino,or hydrocarbyloxide group having up to 18 carbon atoms; E is a bridgingchain of 3 to 8 carbon atoms or 2 to 8 silicon, germanium, or tin atoms,wherein any substituents on atoms of the bridging chain independentlyare H or a hydrocarbyl group having up to 18 carbon atoms; each Xindependently is F; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄; OBR₂ orSO₃R, wherein R is an alkyl or aryl group having up to 18 carbon atoms;or a hydrocarbyloxide group, a hydrocarbylamino group, or ahydrocarbylsilyl group, any of which having up to 18 carbon atoms; m is0, 1, 2, 3, or 4; n is 0, 1, 2, 3, or 4; q is 2 when M is Ti, Zr, or Hf;and q is 1 when M is Cr, Sc, Y, La, or a lanthanide.
 2. The process ofclaim 1, wherein the process is conducted in the presence of addedhydrogen in a range from about 50 ppm to about 1000 ppm; and wherein: aMw/Mn ratio of an olefin polymer produced by the process in the presenceof an olefin comonomer is at least 25% greater than a Mw/Mn ratio of anolefin polymer produced by the process under the same polymerizationconditions without an olefin comonomer; or a Mw of an olefin polymerproduced by the process in the presence of an olefin comonomer is atleast 50% greater than a Mw of an olefin polymer produced by the processunder the same polymerization conditions without an olefin comonomer; orboth.
 3. The process of claim 1, wherein the process is conducted in thepresence of added hydrogen and the olefin comonomer; and wherein: a Mwof the olefin polymer is substantially constant over a range of fromabout 50 ppm to about 1000 ppm added hydrogen; or an activity of thecatalyst composition is substantially constant over a range of fromabout 50 ppm to about 1000 ppm added hydrogen; or both.
 4. The processof claim 1, wherein a molar ratio of olefin comonomer to olefin monomeris in a range from about 0.001:1 to about 0.2:1.
 5. The process of claim4, wherein: the process is conducted in the absence of added hydrogen;and a Mw/Mn ratio of the olefin polymer increases as the molar ratio ofolefin comonomer to olefin monomer increases from about 0.001:1 to about0.06:1.
 6. The process of claim 4, wherein an activity of the catalystcomposition decreases as the molar ratio of olefin comonomer to olefinmonomer increases from about 0.001:1 to about 0.06:1.
 7. The process ofclaim 1, wherein the olefin polymer has: an average of from 0 to about 5short chain branches per 1000 total carbon atoms and a density ofgreater than about 0.92 g/cm³.
 8. The process of claim 1, wherein theprocess is conducted in a batch reactor, slurry reactor, gas-phasereactor, solution reactor, high pressure reactor, tubular reactor,autoclave reactor, or a combination thereof.
 9. The process of claim 1,wherein the olefin monomer is ethylene, and the olefin comonomercomprises propylene, 1-butene, 2-butene, 3-methyl-1-butene, isobutylene,1-pentene, 2-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene,2-hexene, 3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene, 1-octene,1-decene, styrene, or a mixture thereof.
 10. The process of claim 1,wherein the activator comprises an aluminoxane compound, an organoboronor organoborate compound, an ionizing ionic compound, or any combinationthereof.
 11. The process of claim 1, wherein the activator comprises anactivator-support comprising a solid oxide treated with anelectron-withdrawing anion, wherein: the solid oxide comprises silica,alumina, silica-alumina, silica-coated alumina, aluminum phosphate,aluminophosphate, heteropolytungstate, titania, zirconia, magnesia,boria, zinc oxide, a mixed oxide thereof, or any mixture thereof; andthe electron-withdrawing anion comprises sulfate, bisulfate, fluoride,chloride, bromide, iodide, fluorosulfate, fluoroborate, phosphate,fluorophosphate, trifluoroacetate, triflate, fluorozirconate,fluorotitanate, phospho-tungstate, or any combination thereof.
 12. Theprocess of claim 1, wherein the catalyst composition further comprisesan organoaluminum compound having the formula:Al(X^(A))_(p)(X^(B))_(3-p), wherein: X^(A) is a hydrocarbyl; X^(B) is analkoxide or an aryloxide, a halide, or a hydride; and p is from 1 to 3,inclusive.
 13. The process of claim 1, wherein the ansa-metallocenecompound having formula (I) comprises:

or a combination thereof.
 14. A polymerization process, the processcomprising: contacting a catalyst composition with ethylene andoptionally an α-olefin comonomer under polymerization conditions toproduce an ethylene polymer, wherein the catalyst composition comprises:(i) an activator; and (ii) an ansa-metallocene compound having formula(I):E(Cp^(A)R^(A) _(m))(Cp^(B)R^(B) _(n))MX_(q)  (I), wherein: M is Ti, Zr,or Hf; Cp^(A) and Cp^(B) independently are a cyclopentadienyl, indenyl,or fluorenyl group; each R^(A) and R^(B) independently is H or ahydrocarbyl, hydrocarbylsilyl, hydrocarbylamino, or hydrocarbyloxidegroup having up to 18 carbon atoms; E is —SiMe₂—SiMe₂—; each Xindependently is F; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄; OBR₂ orSO₃R, wherein R is an alkyl or aryl group having up to 18 carbon atoms;or a hydrocarbyloxide group, a hydrocarbylamino group, or ahydrocarbylsilyl group, any of which having up to 18 carbon atoms; m is0, 1, 2, 3, or 4; n is 0, 1, 2, 3, or 4; and q is
 2. 15. The process ofclaim 14, wherein: the catalyst composition further comprises anorganoaluminum compound; the activator comprises an activator-supportcomprising a solid oxide treated with an electron-withdrawing anion; andthe α-olefin comonomer comprises 1-butene, 1-hexene, 1-octene, or acombination thereof.
 16. The process of claim 14, wherein the process isconducted in the presence of added hydrogen in a range from about 50 ppmto about 1000 ppm; and wherein: a Mw/Mn ratio of an ethylene polymerproduced by the process in the presence of an α-olefin comonomer is atleast 25% greater than a Mw/Mn ratio of an ethylene polymer produced bythe process under the same polymerization conditions without an α-olefincomonomer; or a Mw of an ethylene polymer produced by the process in thepresence of an α-olefin comonomer is at least 50% greater than a Mw ofan ethylene polymer produced by the process under the samepolymerization conditions without an α-olefin comonomer; or both. 17.The process of claim 14, wherein the process is conducted in thepresence of added hydrogen and the α-olefin comonomer, and wherein: a Mwof the ethylene polymer is substantially constant over a range of fromabout 50 ppm to about 1000 ppm added hydrogen; or an activity of thecatalyst composition is substantially constant over a range of fromabout 100 ppm to about 500 ppm added hydrogen; or both.
 18. The processof claim 14, wherein a molar ratio of α-olefin comonomer to ethylene isin a range from about 0.001:1 to about 0.2:1.
 19. The process of claim18, wherein: the process is conducted in the absence of added hydrogen;and a Mw/Mn ratio of the ethylene polymer increases as the molar ratioof α-olefin comonomer to ethylene increases from about 0.001:1 to about0.06:1.
 20. The process of claim 18, wherein an activity of the catalystcomposition decreases as the molar ratio of α-olefin comonomer toethylene increases from about 0.001:1 to about 0.06:1.
 21. The processof claim 14, wherein: M is Zr or Hf; Cp^(A) is a cyclopentadienyl orindenyl group; Cp^(B) is an indenyl or fluorenyl group; each R^(A) andR^(B) independently is H or a hydrocarbyl group having up to 12 carbonatoms; m is 0, 1, or 2; and n is 0, 1, or
 2. 22. The process of claim21, wherein: M is Zr; Cp^(A) is a cyclopentadienyl or indenyl group;Cp^(B) is an indenyl group; each R^(A) and R^(B) independently is H,methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl,decyl, ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl,nonenyl, decenyl, phenyl, tolyl, or benzyl; and each X independently isF, Cl, Br, I, methyl, benzyl, or phenyl.
 23. A polymerization process,the process comprising: contacting a catalyst composition with ethyleneand an α-olefin comonomer under polymerization conditions to produce anethylene polymer, wherein a Mw of the ethylene polymer is substantiallyconstant over a range of from about 50 ppm to about 1000 ppm addedhydrogen, and/or an activity of the catalyst composition issubstantially constant over a range of from about 100 ppm to about 500ppm added hydrogen, wherein the catalyst composition comprises: (i) anactivator-support comprising a solid oxide treated with anelectron-withdrawing anion; and (ii) an ansa-metallocene compound havingformula (II), (III), (IV), (V), (VI), or (VII):

wherein: M is Ti, Zr, or Hf; each R^(A) and R^(B) independently is a Hor a hydrocarbyl, hydrocarbylsilyl, hydrocarbylamino, orhydrocarbyloxide group having up to 18 carbon atoms; each Xindependently is F; Cl; Br; I; methyl; benzyl; phenyl; H; BH₄; OBR₂ orSO₃R, wherein R is an alkyl or aryl group having up to 18 carbon atoms;or a hydrocarbyloxide group, a hydrocarbylamino group, or ahydrocarbylsilyl group, any of which having up to 18 carbon atoms; eachm is 0, 1, 2, 3, or 4, m′ is 0, 1 or 2, and m″ is 0, 1, or 2; each n is0, 1, 2, 3, or 4, each n′ is 0, 1, or 2, and each n″ is 0, 1, or 2; andeach R^(E), R^(F), R^(G), and R^(H) independently is H or a hydrocarbylgroup having up to 18 carbon atoms.
 24. The process of claim 23, whereinthe process is conducted in the presence of added hydrogen, and wherein:the catalyst composition further comprises an organoaluminum compound;the activator-support comprises fluorided alumina, chlorided alumina,bromided alumina, sulfated alumina, fluorided silica-alumina, chloridedsilica-alumina, bromided silica-alumina, sulfated silica-alumina,fluorided silica-zirconia, chlorided silica-zirconia, bromidedsilica-zirconia, sulfated silica-zirconia, fluorided silica-titania,fluorided silica-coated alumina, sulfated silica-coated alumina,phosphated silica-coated alumina, or any combination thereof; theα-olefin comonomer comprises 1-butene, 1-hexene, 1-octene, or acombination thereof; M is Zr or Hf; each R^(A) and R^(B) independentlyis H, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl,decyl, ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl,nonenyl, decenyl, phenyl, tolyl, or benzyl; each X independently is F,Cl, Br, I, methyl, benzyl, or phenyl; each m is 0, 1, or 2, m′ is 0 or1, and m″ is 0 or 1; each n is 0, 1, or 2, each n′ is 0 or 1, and eachn″ is 0 or 1; and each R^(E), R^(F), R^(G), and R^(H) independently isH, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl,decyl, ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl,nonenyl, decenyl, phenyl, tolyl, or benzyl.